(bug 45784) adapt Lucene configuration file to support beta

beta needs some $wgLucene global variables to point to a different set
of hosts.  This patch splits the old lucene.php to three new files:

 - lucene-common.php : hold the configuration common to both production
   and labs. It ultimately invoke the realm specific file finder to load
   the per realm file (see below)
 - lucene-production.php : hold production settings, copy pasted from
   the previous lucene.php version.
 - lucene-labs.php : points the lucene queries to the lonely search box
   in beta: deployment-search01.pmtpa.wmflabs [10.4.1.81].

Updated the wikitech URL
Removed Brion as a contact in favor of ops/platform

Change-Id: Ia178314dc1c4c4b5e186bbecd481149b55730721
Merge "(bug 45784) adapt Lucene configuration file to support beta"