Hibernate Search implemented

CodeItem is now indexed using and searched using Hibernate Search, which
uses Lucane under the hood. It is much more sophisticated than Postgre
full text search. Future plans may include stop words for every
supported langauge (if I can figure out how to change StopFilterFactory
during runtime). 

All users can search all code. There is no difference between Public,
User or Admin queries. This needs to be changed.

NOTE: Restarting an already running server will give some Lucane errors.
Nothing to worry about. I think...

NOTE: At the time of this upload the database is still indexing
tsv_vectors so it is still possible to search using SearchItem. Database
definition will be changed in the coming week and SearchItem will be
deleted.

NOTE: Lucane index is rebuilt at every server startup. This is
controlled in Hibernate...Filter. 

Searching is easily the most complicated part of the whole app.
Merge branch 'master' of https://github.com/TKasekamp/Veebirakendus.git