Articles can now be switched to Elastic search api.

Lots of test data files, sorry
Merge branch 'master' of github.com:guardian/frontend into elastic-articles
Merge branch 'master' of github.com:guardian/frontend into elastic-articles
parseIsoDateTIme now works with or woithout millis
new Testdata
Merge pull request #2261 from guardian/elastic-articles

Articles can now be switched to Elastic search api.