remove win-oracleJDK11 and Linux-OracleJDK11 on travis-ci temporary.

* add sync docu

* modify sync docu according to pr review

* multi-directories avoid using disk without space

* fix that MManager is incorrectly recovered when system reboots

* clean overflow files when storage group is deleted

Fix a doc bug of QuickStart.md

The word colomn should be column.

simplify Path construction, which improves 17% write speed

[IOTDB-107]fix missing wal log node after recovery

* organize properties

* add time unit

* fix mistakes in doc

* use a more elegant way to return results of Authorization queries like 'LIST USERS'

* fix tests

* improve client display

* fix a test in windows

* fix client display

* keep stack trace when logging or throwing an Exception

* fix jira issue 100

* remove useless code

* modify logic: add params in ReadOnlyTsFile's query function not in constructor

* remove loadMode; update the calculation of remaining time ranges

* fix sonar

* refactor iotdb code for cluster

* delete useless code

* fix issues according to pr reviews

* fix issues according to pr reviews

* delete useless code in MGraph

* delete useless map in Metadata

* delete useless map in Metadata

* update

* update

* fix some issues

* update combineMetadatas() in Metadata

* update combineMetadatas() in Metadata

* remove closeClusterService

* print debug information about the start and end position of chunkgroupMetadata

fix a bug in TsFile-Spark-Connector

* add logical part for global time filters from partition problem

* Update README.md, doc, dependency version pom, .travis.yml

* modify scala version to 2.11.8 and restrict java version to 8, change scalatest version from 2.12 to 2.1

* refactor query resource count

* format code

* fix a bug

* remove lock

* fix in proper hashcode methods in processors

try to release memory asap in ReadOnlyMemChunk

* BufferWriteProcessor: remove fileName (because insertFilePath is enough)

* TsFileResource: remove relativePath; using autoRead for automatically initialize startTimeMap and endTimeMap

* IMemTable, AbstractMemTable: add returned value of delete()
* TsRecord: change dataPoints from List to Array. And in many other classes, if Array is enough, then replace List<> by Array.

* For insertion, add a new method write(long time, Object value) to replace write(long time, String value), because the latter has to call a switch-case and something like Integer.valueOf(value).

* move recovery function from TsFileSequenceReader to its subclass

* add append option in TsFile writer and add a subclass of TsFileSequenceReader for supporting auto repair

* fix stream unclosed when exception occurs when creating TsFileReader

* reject writes when the memory is dangerous

* faster memtable.getSortedTimeValuePairList

* reduce memory cost when sorting data in memory

* fix equals() method in InsertPlan

* make TsFileWriter as AutoClosable; make TsFileReadWriteTest more concise

* make stop tsfileProcess more safe

* add DisabledMemController

* fix method name

* reuse BufferWriteProcessor and OverflowProcessor to reduce memory waste.

* fix initialized isClose

* fix reopen

* fix closed Overflowprocessor calling switchWorkToMerge

* reimplement MTree.toString() by JSON
add MManager.combineMetadataInStrings(String[] metadatas) for cluster module

* move add TIMESERIES HEADER from MGraph to TSServiceImpl
fix bug when MTree combine JSONObjects

* update timeseries metadata format in docs

supporting travis + win +jdk8

* fix that the damaged log will be skipped if it is the only log

* add error log

* fix test