Updated ruby version to 2.1.1.
Import WordMarkings with the activerecord-import gem.
Refactored marking import code into class methods on the model.
Moved the method to process prism content into the model.

Now with tests!
Don't import markings beyond the length of the prism.
Don't allow multiple indexes.

This isn't enforced in the database, and because we want to be able to
bulk load the indexes later, we have to load them all at once.
Removed trailing whitespace.
Merge branch 'highlight-post' into develop

Conflicts:
	app/controllers/prisms_controller.rb
Removed spec tags for current.