Miscellaneous fixes

  o RooWorkspace

    - Fix compiler error/warning in getSnapshot()


  o RooAbsTestStatistic

    - Add bookkeeping for MP set member that will calculated extended term

    - in setMPSet() assing set number for MP calculation based on checksum
      of object name modulo nset to obtain more or less even spread of
      extended term calculations over processes in MP mode


  o RooNLLVar

    - Calculated extended term in designated MP set instead of
      set with _firstEvent=0. This also fixes a bug in NumCPU(n>1)
      calculations of HistFactory models with 1-bin channels
      where the extended term was unintentionally evaluated
      in >1 MP set.

  o RooAbsReal

   - Add accessor getForceNumInt()


git-svn-id: https://root.cern.ch/svn/root/branches/v5-34-00-patches@49103 27541ba8-7e3a-0410-8455-c3a389f83636