Transfer and edit full text indexing recipe

[bess]

Descriptive summary of request

I want a guide about how to add full-text indexing to Hyrax.

Existing Documentation

There is a guide written for Sufia, here: https://github.com/samvera/hydra/wiki/Recipe%3A-Add-full-text-indexing-to-your-app

However, it is out of date and not tested against Hyrax.

Expected Document

I expect to see a "How to add full text indexing to Hyrax" document, which is in samvera.github.io and follows our common style conventions. I expect the other one to be removed.