* Fixed bugs with viz in exploreV2
Done:
- fix typo in pie viz
- add metrics/groupby to dist_bar viz
- fix typo in heatmap viz
- add big_number_total to viz
- fixed problem with fetching columns for datasource
- add sqlaTimeSeries to viz
- change row_limit and limit from number to strings so that we
don't need to parse integers in bootstrap data
* Fix python tests
* Added order_bars checkbox for dist_bar viz
* Move datasource from global store object to form_data
* Moved datasource_id and datasource_name to form_data
* Refetch defaultFormData when switching datasource
* Fixed js tests
* Get query buttonw working in explorev2
- Create new endpoint for updating explore viz
- Send over new form_data when query button is pressed
* Added endpoint test
* Changes based on comments
* Added docstring for endpoint, and query spec
* Remove white space around docstring
* Added different Select Fields
- Switched FormGroup to react-select
- Added multi and freeform to select, now it can take customized user
input and insert it as options
* Fixed tests
* Small nit based on comments
* Change in files
* Renamin files and folders
* cleaning up a single piece of lint
* Removing boat picture from docs
* add superset word mark
* Update rename note in docs
* Fixing images
* Pinning datatables
* Fixing issues with mapbox-gl
* Forgot to rename one file
* Linting
* v0.13.0
* adding pyyaml to dev-reqs
* Link fields to store by firing setFormData action
* Moved onChange to ControlPanelsContainer, retrieve defaultFormData from fields in store
* Pass data from store to checkbox/select/text Field
* Fixed tests
* Changed reducer back to old Object.assign() style
* pass field options in viz json
* move field options to fetch_datasource_metadata
* on control panels container mount, fetch datasource meta data and set dynamic field choices
* render options for select fields
* use component class rather than sic
* fix linting
* fix whitespace
* delete unused var
* only render fields once datasource meta has returned
* fix typo
* add datasources and fix column formatting
* fix tests
* never used function
* fix tests
* add test for fetch_datasource_metadata
* remove unneeded props