Item11664: 

   * fixed SOLR_FILTER preference variable resulting in a syntax error in a syntax error even though the filter is okay
   * don't cache stringified text/plain 
   * disabling {EnableOnRenameUpdates} now by default as moving stuff from/to topics with lots of attachments (1000+) becomes
     potentially slow
   * use relative urls where possible
   * use a nice process prio for solrjobs 



git-svn-id: http://svn.foswiki.org/trunk/SolrPlugin@16700 0b4bb1d4-4e5a-0410-9cc4-b2b747904278