Import fixes / new functionality from branches/dev/proof:

   - proof/proofplayer/src/TPacketizerAdaptive.cxx
      Implement the classic strategy of the TPacketizer in TPacketizerAdaptive.
      The strategy can be changed from adaptive (default) to TPacketizer with:
      "PROOF_PacketizerStrategy" parameter to PROOF

   - proof/proofplayer/src/TProofPlayer.cxx
      Fixed error messages for 'MissingFiles' and 'FailedPackets' lists.
      Improve fault detection by creating a list of failed packets upon a mismatch
      in the expected and actual number of processed events; the list is added to
      the output list.

   - proof/proofplayer/src/TVirtualPacketizer.cxx
      Make sure that something has been processed before setting kIsDone.
      Improve fault detection by creating a list of failed packets upon a mismatch
      in the expected and actual number of processed events; the list is added to
      the output list.

   - proof/proofplayer/inc/TVirtualPacketizer.h
      Improve fault detection by creating a list of failed packets upon a mismatch
      in the expected and actual number of processed events; the list is added to
      the output list.

   - proof/proofplayer/inc/TPacketizerAdaptive.h
      Implement the classic strategy of the TPacketizer in TPacketizerAdaptive

   - proof/proof/src/TProofServ.cxx
      Fixes:
       + option string: "stageOnly" --> "stagedOnly".
       + add parenthesis to avoid a warning after the previous patch.
       + remove the objects added to the missingFiles in TDSet::Add from the 'dataset'
         before deleting it
       + fixed an error HandleCheckFile ('kPROOF_WorkDir' instead of 'kPROOF_PackDir').
       + make fCacheDir and fPackageDir controllable via directive
       + in TProofServ::ErrorHandler: do not create the related additional buffer if
         not logging to syslog
      Added functionality:
       - add possibility to flag an "Info" message as service message using
         the prefix "|Svc" in the location field; e.g.

            Info("SetupCommon|Svc", "Test of SvcMsg");

         will produce something like

            09:28:24  6892 Mst-0 | SvcMsg in <TXProofServ::SetupCommon>: Test of SvcMsg

         This is needed to be able in the future to filter-out messages needed
         by some services (e.g. the forthcoming memory checker) which should not be
         displayed by default.

   - proof/proofd/src/XrdProofSched.cxx
      Improve the calculation of the number of workers to assign by using fMinForQuery
      as a minimum.
      Fix the length of method separators.
      Fix signed/unsigned warning.


git-svn-id: http://root.cern.ch/svn/root/trunk@23986 27541ba8-7e3a-0410-8455-c3a389f83636