Adds the command line option "--concurrent-events=N" which enables individual
control of the number of concurrent events as well as the number of threads in
an AthenaMT job.

If --concurrent-events OR --threads is used, the job is assumed to be MT.

If neither is set, then the job is not setup as AthenaMT.

If only one of --concurrent-events or --threads is used, the other takes the same
value (ie, same number of concurrent events as threads).

Both --concurrent-events and --threads can also be set simultaneously

Added AthBeginSeq and AthEndSeq sandwitching around AthAlgSeq to
handle Incident Processing Algorithms

2017-01-25 Steve Farrell <Steven.Farrell@cern.ch>
        * Setting _threaded attribute of PyROOT-bound C++ methods in
          AthAppMgr in order to release the python GIL. The flag is set
          according to ConcurrencyFlags.NumThreads() and is set for the
          initialization, executeRun, and finalization calls.
        * Tagging: AthenaCommon-03-03-21

	* Adding 'base release' to the dictionary returned by release_metadata (required by the Obsolete Geometry mechanism)

2016-03-15  Frank Winklmeier  <fwinkl@cern>
	* python/PropertyProxy.py: Remove unnecessary string formatting in _isCompatible (twice faster)
	* tag AthenaCommon-03-03-11

2016-02-16  Charles Leggett
	* create ConditionStore for threaded jobs
	* tag AthenaCommon-03-03-10

M       python/AtlasThreadedJob.py

2016-02-09  Vakho Tsulaia  <tsulaia@cern.ch>

	* Introducing new command-line option for athena.py: --profile-python (OBO Wim)
	* tag AthenaCommon-03-03-09

	* Tagging AthenaCommon-03-03-03
	* Adding an overlay task to the DetFlags

2015-06-04  Charles Leggett
	* tag AthenaCommon-03-03-02
	* add common concurrency opts (nProc, nThread) to ConcurrencyFlags
	  jobProps
	* added CONFIGURATION_ERROR to ExitCodes (0x09)

A       python/ConcurrencyFlags.py
M       python/ExitCodes.py
M       python/AtlasThreadedJob.py
M       python/AthOptionsParser.py
M       share/Execution.py
M       share/Preparation.py

2015-06-01  Charles Leggett
	* tag AthenaCommon-03-03-01
	* on behalf of John Chapman
...
(Long ChangeLog diff - truncated)