[Bug 894686] Localized search

This adds locale specific analyzer settings to the KB search.

This is a change to the ES indexes, so it is structured as a two step change. Step one updates ES_WRITE_INDEXES and makes the indexing changes, and step two updates ES_READ_INDEXES and updates the search code. For local testing, you can use take both commits as a single unit, though they should work and be tested separately as well.

To test: reindex the KB. (`./manage.py esreindex --delete --criticalmass` should work). Do searches. It should all work. Do searches in a language that isn't English and you should get stemming and stop word support. The easiest way I have found to see this is to search for "tienos" in spanish, and notice that documents that contains "tienes" are ranked highly (those words are conjucations of "to have", so should be stemmed together)

I'm currently writing tests for this, but they are a little involved, so I wasn't sure I would have them done today. I hoped I could get some review on this before the weekend.

f?