Fixes for Gxs msg retrieval:

msgId retrieval fixed, including incorrect stack mtx lock
msgRelatedId retrieval fixed, mem leak removed (did not clean meta)
msg data retrieval fixed 

added related tests 

RsThread::start now initialises mIsRunning to true, needed to unit tear
down on gxs test system.


git-svn-id: http://svn.code.sf.net/p/retroshare/code/branches/v0.5-gxs-b1@5471 b45a01b8-16f6-495d-af2f-9b41ad6348cc

libretroshare/src/gxs/rsdataservice.cc

@@ -778,6 +778,7 @@ int RsDataService::retrieveNxsMsgs(const GxsMsgReq &reqIds, GxsMsgResult &msg, b
             {
                 RsGxsMsgMetaData* meta = *meta_lit;
                 delete meta;
+                meta_lit = msgMetaV.erase(meta_lit);
             }
         }
     }