Enable logParser to handle jO made with sherpaTarCreator [skip modfiles]

This enables logParser to see if the jO is produced with sherpaTarCreator and if it is, it will disable the checks associated to nEventsPerJob.

Technically this has been implemented as a Sherpa-specific test and only searches for the presence of the work sherpaTarCreator anywhere in the log.generate. This is perhaps too loose and can be tailored according to our needs so @fsiegert and @cgutscho can comment - the point is that you now have all the freedom to define what you print out as an indication of sherpaTarCreator being used ;)

Tested with 950006 that Chris provided after tweaking the file to produce an ERROR and before the change I get this:

- CountHepMC Events passing all checks and written =   10  <-- ERROR: This is not equal to nEventsPerJob=100 
...
---------------------
 Summary:
---------------------
Errors : 2 , Warnings : 2   -> Errors encountered! Not ready for production! 

and after the change I get this

-------------------------
Generator specific tests: Sherpa(v.2.2.8p3)
-------------------------
- retried events Beam_Remnants =   0.9 % 
- retried events Jet_Evolution:CSS =   1 % 
- jO created with sherpaTarCreator   - will disable nEventsPerJob checks 
...
- CountHepMC Events passing all checks and written =   10  <-- WARNING: This is not equal to nEventsPerJob=100 
...
---------------------
 Summary:
---------------------
Errors : 1 , Warnings : 3   -> Errors encountered! Not ready for production! 

In this case the error is coming from a high memory consumption so there is still 1 ERROR remaining but the point is that the ERROR from nEventsPerJob is reduced to a WARNING (we might even want to reduce it even further to an INFO)

Closes #35 (closed)