Added cmd line arguments --eventParameters, --runNumberOffset and --eventNumberOffset to steer lcio output parameters

Adding the helper to allow reading an MCParticle collection with an arbitrary name

whitespace to emulate the output from DD4hep
Solves #56

  - to activate run ddsim with:
     --part.enableDetailedHitsAndParticleInfo

 - add option to enable debug output actions for hits from Markus

Add Helper Input and GuineaPig for further expansions in the future

Set on the command line with

   --guineapig.particlesPerEvent=123

or in the steering file

   SIM.guineapig.particlesPerEvent=123

This reverts commit 70feca4742a0721bdbe7197de1a33eb878a63799.

as we are now potentially changing the random seed we need to initialize it before the output file, because we write the variables to the outputfile at this point

Add option to enable eventSeed plugin
Add possibility to create switches automatically, this does not allow 'choice' so we need to if/else the whole function call add_argument

Need to return the value
Kept DDg4ParticleGun from working

Cannot use PrimaryHandler together with either of these (particles are created twice)
Thanks to S.Lukic for pointing out the problem

Move consistency checks to separate function for better readability

DDSim: Add functionality to enable geant4gun and geant4 particle general source. Needs DD4hep Revision 2128

Add example macro file to use gun or general particle source

Do not print error messages when dumping SteeringFile or parameters
Fix crash when dumping steeringfile

DDSim: Add logic to add help for non-property helper variables, add logic to add choices for all helper options