[scripts] remove quickstart scripts

- we already decided to host them on the website
- not really useful and they need maintenance
- having the snapshot quickstart in the source is against Apache rules

This closes #822.

flink-quickstart/quickstart-SNAPSHOT.sh

-#!/usr/bin/env bash
-
-################################################################################
-#  Licensed to the Apache Software Foundation (ASF) under one
-#  or more contributor license agreements.  See the NOTICE file
-#  distributed with this work for additional information
-#  regarding copyright ownership.  The ASF licenses this file
-#  to you under the Apache License, Version 2.0 (the
-#  "License"); you may not use this file except in compliance
-#  with the License.  You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-#  Unless required by applicable law or agreed to in writing, software
-#  distributed under the License is distributed on an "AS IS" BASIS,
-#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-#  See the License for the specific language governing permissions and
-# limitations under the License.
-################################################################################
-
-
-PACKAGE=quickstart
-
-mvn archetype:generate								\
-  -DarchetypeGroupId=org.apache.flink				\
-  -DarchetypeArtifactId=flink-quickstart-java		\
-  -DarchetypeVersion=0.9-SNAPSHOT					\
-  -DgroupId=org.myorg.quickstart 					\
-  -DartifactId=$PACKAGE								\
-  -Dversion=0.1										\
-  -Dpackage=org.myorg.quickstart 					\
-  -DinteractiveMode=false							\
-  -DarchetypeCatalog=https://repository.apache.org/content/repositories/snapshots/
-
-#
-# Give some guidance
-#
-echo -e "\\n\\n"
-echo -e "\\tA sample quickstart Flink Job has been created."
-echo -e "\\tSwitch into the directory using"
-echo -e "\\t\\t cd $PACKAGE"
-echo -e "\\tImport the project there using your favorite IDE (Import it as a maven project)"
-echo -e "\\tBuild a jar inside the directory using"
-echo -e "\\t\\t mvn clean package"
-echo -e "\\tYou will find the runnable jar in $PACKAGE/target"
-echo -e "\\tConsult our website if you have any troubles: http://flink.apache.org/community.html#mailing-lists"
-echo -e "\\n\\n"
-

flink-quickstart/quickstart-scala-SNAPSHOT.sh

-#!/usr/bin/env bash
-
-################################################################################
-#  Licensed to the Apache Software Foundation (ASF) under one
-#  or more contributor license agreements.  See the NOTICE file
-#  distributed with this work for additional information
-#  regarding copyright ownership.  The ASF licenses this file
-#  to you under the Apache License, Version 2.0 (the
-#  "License"); you may not use this file except in compliance
-#  with the License.  You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-#  Unless required by applicable law or agreed to in writing, software
-#  distributed under the License is distributed on an "AS IS" BASIS,
-#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-#  See the License for the specific language governing permissions and
-# limitations under the License.
-################################################################################
-
-
-PACKAGE=quickstart
-
-mvn archetype:generate								\
-  -DarchetypeGroupId=org.apache.flink 				\
-  -DarchetypeArtifactId=flink-quickstart-scala		\
-  -DarchetypeVersion=0.9-SNAPSHOT					\
-  -DgroupId=org.myorg.quickstart					\
-  -DartifactId=$PACKAGE								\
-  -Dversion=0.1										\
-  -Dpackage=org.myorg.quickstart					\
-  -DinteractiveMode=false							\
-  -DarchetypeCatalog=https://repository.apache.org/content/repositories/snapshots/
-
-#
-# Give some guidance
-#
-echo -e "\\n\\n"
-echo -e "\\tA sample quickstart Flink Job has been created."
-echo -e "\\tSwitch into the directory using"
-echo -e "\\t\\t cd $PACKAGE"
-echo -e "\\tImport the project there using your favorite IDE (Import it as a maven project)"
-echo -e "\\tBuild a jar inside the directory using"
-echo -e "\\t\\t mvn clean package"
-echo -e "\\tYou will find the runnable jar in $PACKAGE/target"
-echo -e "\\tConsult our website if you have any troubles: http://flink.apache.org/community.html#mailing-lists"
-echo -e "\\n\\n"
-

flink-quickstart/quickstart-scala.sh

-#!/usr/bin/env bash
-
-################################################################################
-#  Licensed to the Apache Software Foundation (ASF) under one
-#  or more contributor license agreements.  See the NOTICE file
-#  distributed with this work for additional information
-#  regarding copyright ownership.  The ASF licenses this file
-#  to you under the Apache License, Version 2.0 (the
-#  "License"); you may not use this file except in compliance
-#  with the License.  You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-#  Unless required by applicable law or agreed to in writing, software
-#  distributed under the License is distributed on an "AS IS" BASIS,
-#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-#  See the License for the specific language governing permissions and
-# limitations under the License.
-################################################################################
-
-
-PACKAGE=quickstart
-
-mvn archetype:generate								\
-  -DarchetypeGroupId=org.apache.flink				\
-  -DarchetypeArtifactId=flink-quickstart-scala		\
-  -DarchetypeVersion=0.8.1							\
-  -DgroupId=org.myorg.quickstart					\
-  -DartifactId=$PACKAGE								\
-  -Dversion=0.1										\
-  -Dpackage=org.myorg.quickstart					\
-  -DinteractiveMode=false
-
-#
-# Give some guidance
-#
-echo -e "\\n\\n"
-echo -e "\\tA sample quickstart Flink Job has been created."
-echo -e "\\tSwitch into the directory using"
-echo -e "\\t\\t cd $PACKAGE"
-echo -e "\\tImport the project there using your favorite IDE (Import it as a maven project)"
-echo -e "\\tBuild a jar inside the directory using"
-echo -e "\\t\\t mvn clean package"
-echo -e "\\tYou will find the runnable jar in $PACKAGE/target"
-echo -e "\\tConsult our website if you have any troubles: http://flink.apache.org/community.html#mailing-lists"
-echo -e "\\n\\n"
-

flink-quickstart/quickstart.sh

-#!/usr/bin/env bash
-
-################################################################################
-#  Licensed to the Apache Software Foundation (ASF) under one
-#  or more contributor license agreements.  See the NOTICE file
-#  distributed with this work for additional information
-#  regarding copyright ownership.  The ASF licenses this file
-#  to you under the Apache License, Version 2.0 (the
-#  "License"); you may not use this file except in compliance
-#  with the License.  You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-#  Unless required by applicable law or agreed to in writing, software
-#  distributed under the License is distributed on an "AS IS" BASIS,
-#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-#  See the License for the specific language governing permissions and
-# limitations under the License.
-################################################################################
-
-
-PACKAGE=quickstart
-
-mvn archetype:generate								\
-  -DarchetypeGroupId=org.apache.flink				\
-  -DarchetypeArtifactId=flink-quickstart-java		\
-  -DarchetypeVersion=0.8.1							\
-  -DgroupId=org.myorg.quickstart					\
-  -DartifactId=$PACKAGE								\
-  -Dversion=0.1										\
-  -Dpackage=org.myorg.quickstart					\
-  -DinteractiveMode=false
-
-#
-# Give some guidance
-#
-echo -e "\\n\\n"
-echo -e "\\tA sample quickstart Flink Job has been created."
-echo -e "\\tSwitch into the directory using"
-echo -e "\\t\\t cd $PACKAGE"
-echo -e "\\tImport the project there using your favorite IDE (Import it as a maven project)"
-echo -e "\\tBuild a jar inside the directory using"
-echo -e "\\t\\t mvn clean package"
-echo -e "\\tYou will find the runnable jar in $PACKAGE/target"
-echo -e "\\tConsult our website if you have any troubles: http://flink.apache.org/community.html#mailing-lists"
-echo -e "\\n\\n"
-
-