Make sure to delete existing/to save translations after each test (bug 1076992)

ESTestCase inherits from TransactionTestCase and therefore we need to
cleanup after ourselves, and that includes translations.

Also, wrap tests that create translations in a TestCase class
Merge pull request #2782 from diox/fix-translations-flaky-test

Make sure to delete existing/to save translations after each test (bug 1076992)
generate packaged apps (bug 1065579)
Merge pull request #2712 from washort/1065579

Generate fake packaged apps (bug 1065579)
update screenshot; bug 1111028
Merge pull request #2784 from clouserw/1111028

replace screenshot; bug 1111028
Add indexation on first run of docker env
Send 'restofworld' to basket as '' (bug 1112659)
Fix CORS in devhub test receipts (bug 1104371)

This also fixes the CORS decorator which was
previously broken for OPTIONS requests.
Merge pull request #2787 from mstriemer/newsletter-restofworld-blank-1112659

Send 'restofworld' to basket as '' (bug 1112659)
Merge pull request #2786 from kumar303/dev-cors

Fix CORS in devhub test receipts (bug 1104371)
add in desktop payments flag (bug 1109191)
Merge pull request #2788 from andymckay/1109191

add in desktop payments flag
Trigger reindex on app when changing feature requirements (bug 1112625)
add a contribute.json file (bug 1074452)
Merge pull request #2783 from diox/reindex-when-changing-features

Trigger reindex on app when changing feature requirements (bug 1112625)
Don't use --index=apps
Merge pull request #2785 from muffinresearch/add-indexation-docker-first-run

Add indexation on first run of docker env