bug 839214 - add celery tasks for es indexing

elasticutils tasks broken; add tasks in search app

test
bug 839214 - live indexing into elastic search

Code borrowed in large part from mozilla/fjord

update elasticutils, using pyelasticsearch with updated requests library

update test-utils library to eagerly test celery tasks
update tests for new test-utils
(some) code cleanup
remove obsolete search tests

don't ignore settings_test
new bulk reindex command

remove sphinx modules from search app
waffle search view to ES
disable ES_LIVE_INDEX during tests
Improve support for the user's language preferences.
Fix ValueError: too many values to unpack.
Fix NameError: global name 'ranked' is not defined.
Fix bug 850656: Set based_on field correctly
Fix bug 812728: Rev dash - Add filter for changes from new users
fix test mocks to match new requests version
JS efficiency and cleanup
Check if empty, use MIN(), explain query, correct id
Merge pull request #933 from darkwing/auto-update

JS efficiency and cleanup
Merge pull request #931 from Elchi3/new-docs-850656

Fix bug 850656: Set based_on field correctly
Merge pull request #932 from Elchi3/dash-newusers-812728

Fix bug 812728: Rev dash - Add filter for changes from new users
bug 812728 - waffle new user filter