Tests

Adds support for json-based widgets/mashups #171

Job	Run time
build	14s
js-unit-tests	53s
django-search-indexes-tests (Elasticsearch)	1m 22s
django-search-indexes-tests (Solr)	1m 45s
django-selenium-tests	40m 21s
django-unit-tests (2.0, 3.7)	12m 54s
django-unit-tests (2.0, 3.8)	16m 18s
django-unit-tests (2.0, 3.9)	15m 42s
django-unit-tests (2.0, 3.10)	16m 19s
django-unit-tests (2.1, 3.7)	13m 8s
django-unit-tests (2.1, 3.8)	16m 32s
django-unit-tests (2.1, 3.9)	16m 7s
django-unit-tests (2.1, 3.10)	16m 36s
django-unit-tests (2.2, 3.7)	13m 10s
django-unit-tests (2.2, 3.8)	16m 58s
django-unit-tests (2.2, 3.9)	15m 58s
django-unit-tests (2.2, 3.10)	16m 10s
finish	8s
	3h 50m 35s

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