* Making thrift, pyhive and tableschema as extra_requires

Looking at the dependency tree for license related questions, I noticed
that tableschema had a huge tree, and only people running Hive really
need it. Making this as well as pyhive and thrift optional.

Also bumping some python dependencies

* Run pip-compile

* Removing refs to past.builtins (from future lib)

* Add thrift

* update contributing based on SIP-13

* update link

* add labels instruction

* minor edit

* minor edit

* update table of content

* Add ASF header and update insructions

* update table

* update text

* This renames the package to apache-superset instead of superset.
  This is required.
* It sets the download location to the official ASF repositories

'Add database' grid refers to SQLAchemy docs, where database URL format is described. 
Documentation for 1.0 does not exist on https://docs.sqlalchemy.org/, which results in 404 when following the current URL.
The link is fixed taking into account [SQLAlchemy 1.2](https://github.com/apache/incubator-superset/blob/master/requirements.txt#L87) as a project dependency.

This reverts commit 5055157b.

* Merge heads

* Add ASF header

* Allow empty results in Hive (from SET, eg)

* Remove patch

* Merge heads

* Delete merge heads

* Insert space after auto complete

* Fix autocomplete with space

* Expose more columns in saved queries API

* Add extra column to SavedQuery

* Add ASF header

* Conditionally mutate and quote sqla labels decouple sqla logic from viz.py

* Prefix hashed label with underscore if bigquery label exceeds 128 chars

* Add comments for label cache

* Rename to mutated_labels and simply

* Rename mutated_label to get_label and simplify make_label_compatible in db_engine_specs

* Add note about deterministic and unique mutated labels

* add hash to label that has been prefixed with underscore

* Fix PEP8 escape warning

* Fix DeckPathViz get_metric_label call

* [cosmetic] remove margin-bottom on dropdowns

react-select components have been added 15px bottom-margin without a
good reason. Other controls like text or checkboxes don't have that,
making Selects look non-standard, add making the control list too
sparse.

My perspective is that all controls should have the same
padding/margins.

* Adding a few licenses

* More ASF licenses

* html

* removing from vendors

* [cosmetic] CRUD's list from 'Add Filter' to 'Filter Results'

* Add global new button

* A better viz type selector

* lint

* Move view to new module, add unit test

* 'Filter Results' -> 'Filter'

* db merge

* Filter -> 'Filter List'

* Ignore empty lines

* Fix unit tests

* Use stripped

* Fix another unit test

* add more shims
* update package-lock.json

* Fix Text field to edit SQL snippet of a metric is not large enough for entire snippet
* Fix Airbnb bug PRODUCT-62223 

* [WiP] deprecate auto-generated metrics & fix examples

Picking up some leftover pieces not needed anymore since the
MetricsControl

* db merge

* db merge

* fix migration

* Creating metrics required for tests

User @ravi on Slack reported issues trying to use url_param jinja macro.
explore_json would raise a "KeyError: 'url_params'".

The feature works when a parameter is passed, but fails hard when none
are passed.

I improved the docstring on the macro as well.

* Bump some of the requirements-dev.txt

* addressing comments

* Add license headers

* reabased

* lint

* Removing licenses from vendors folder

* [table editor] allow selecting physical table

* Using classes for padding

* Fix: https://github.com/apache/incubator-superset/issues/6590, also depends on https://github.com/apache-superset/superset-ui/pull/71

* Bumped version of superset-ui-connector

* Added @babel/polyfill import

* Reset mock history before each test, not after each test

* Update CONTRIBUTING.md

* Update CONTRIBUTING.md

* revert 848

* nit

* add fix for odbc+mssql

* fix for pylint/pep8

Not needed anymore in py3

Fix permission issue.

* Fix scheduled reports for mysql

* Really revert setup.py

* Fix after rebase

* Add NOTICE file and include initial third party licenses

* Add to manifest

* Use txt

* Fix notice

* #6588 Clear all other query tabs

* Improve SQLEditor methods bind

* Update loop syntax

* [README] use a numbered list instead of bullets for org list

* Add companies frmo https://stackshare.io/superset/in-stacks

* Improve Filter Box

* layout tweaks