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Major improvements:
* 647: Upload json files as data sources (in addition to CSV and SQLite files). Both 'normal'
json files, and files structured as a list of json objects (one json object per line) are supported.
* 643: Addresses 640 (Snowflake support). Additionally, supports an "extras" field on the
userspace DatabaseConnection object, which allows for arbitrary additional connection
params to get added. This allows engine-specific (or just more obscure) settings to
get injected into the connection.
* 644: Dockerfile and docker-compose to run the test_project. Replaces the old start.sh script.
Minor improvements:
* 647: In the schema explorer, clicking on a field name copies it to the clipboard
* 647: Charts are limited to a maximum of 10 series. This significantly speeds up rendering
of 'wide' result-sets when charts are enabled.
* 645: Removed pie charts, added bar charts. Replaced Seaborn with Matplotlib
because it's much lighter weight. Pie charts were overly finicky to get working.
Bars are more useful. Will look to continue to expand charting in the future.
* 643: After uploading a csv/json/etc, the resulting connection is highlighted in the
connection list, making it much clearer what happened.
* 643: Fixed some bugs in user connection stuff in general, and improved the UI.
Bugfixes and internal improvements:
* 647: Robustness to the user uploads feature, in terms of the UI, error handling and logging, and test coverage.
* 648: Backwards migration for 0016_alter_explorervalue_key.py
* 649: Use a more reliable source of the static files URL
* 635: Improved test coverage in tox, so that base requirements are properly used.
This would have prevented (for example) issue 631. Additionally, introduced a test
to verify that migrations are always generated, which would have prevented 633.
* 636: Output rendering bugfix.
* 567: Upgrade translate tags in templates to more modern style.