Merge remote-tracking branch 'origin/theming' into staging

...ebsite/dashboard/migrations/0003_widgetinstance_height.py

django/website/dashboard/models.py

django/website/dashboard/static/dashboard/dashboard.css

...site/dashboard/templates/dashboard/basic-text-widget.html

django/website/dashboard/templates/dashboard/dashboard.html

django/website/dashboard/tests/dashboard_view_tests.py

django/website/dashboard/tests/widgetinstance_model_tests.py

django/website/dashboard/views.py

django/website/dashboard/widget_pool.py

django/website/hid/__init__.py

django/website/hid/static/flot/API.md

django/website/hid/static/flot/CONTRIBUTING.md

django/website/hid/static/flot/FAQ.md

django/website/hid/static/flot/LICENSE.txt

django/website/hid/static/flot/Makefile

django/website/hid/static/flot/NEWS.md

django/website/hid/static/flot/PLUGINS.md

django/website/hid/static/flot/README.md

...e/hid/static/flot/examples/ajax/data-eu-gdp-growth-1.json

...e/hid/static/flot/examples/ajax/data-eu-gdp-growth-2.json