o Use the lexicon's pipeline (e.g., case flattening, stop word removal, etc.)

o Forward-port from 2.12 branch.

A hint for the next person who gets very confused when importing something a second time doesn't work.

Thanks to Vladimir Patukhov for the patch.  

o This directory is searched for 'App.Extensions' lookups.  Thanks to Rodrigo
  Senra for the patch.