* split reducer logic for ExploreViewContainer

* fix saveModal component and unit tests

* revert changes in SaveModal_spec.
will make another commit just to improve test coverage for SaveModal component.

* improve test coverage for explore view components:
- SaveModal component
- URLShortLinkButton

* remove comment-out code

* [bugfix] wrong 'Cant have overlap between Series and Breakdowns' (#3254)

* [explore] make edit datasource a basic link (#3244)

* Relying on FAB for font-awesome.min.css (#3261)

* Modernize SQLA pessimistic handling (#3256)

Looks like SQLAlchemy has redefined the best practice around
pessimistic connection handling.

* [webpack] break CSS and JS files while webpackin' (#3262)

* [webpack] break CSS and JS files while webpackin'

* cleaning up some templates

* Fix pylint issue

* import logging (#3264)

* [bugfix] preserve order in groupby (#3268)

Recently in
4c3313b
I introduced an issue where the order of groupby fields might change.

This addresses this issue and will preserve ordering.

* Explicitly add Flask as dependancy (#3252)

* Use sane Celery defaults to prevent tasks from being delayed (#3267)

* Improve the chart type of Visualize in sqllab (#3241)

* Improve the chart type of Visualize in sqllab & Add some css & Fix the link address in the navbar

* add vizTypes filter

* Set default ports Druid (#3266)

For Druid set the default port for the broker and coordinator.

* [explore] Split large reducer logic in ExploreViewContainer (#3088)

* split reducer logic for ExploreViewContainer

* fix saveModal component and unit tests

* revert changes in SaveModal_spec.
will make another commit just to improve test coverage for SaveModal component.

* remove comment-out code

* fix merge confilicts