Event display: fixes for event based mode + new event display for timeslices w/ events + example for mCBM

• Event display for Event based or timeslices with single events:
  • Fix crash due to uninitialized var + related modern C++ updates
  • Add draw of TOF part of global track if present
• Add new event display for CbmTimeslice with CbmEvent array
• Add example of usage

Still missing:

• Support in macro for geometry alignment
• Fix visibility levels of the various detectors either in the macro or in the main manager class
• Change Multi-view to have Z-X instead of X-Y, need more changes relative to FairEventManager base class (in addition to the 3D and Z-Y which are ok)
• Howto file explaining where to find the TS/Event selection, what the buttons do (should be obvious from their name/tag but better safe than sorry), ...
• Code cleanup + includes cleanup
• TOF tracking support, tried to do it but as Objects are TofTracklets and not TofTracks, gave up after 1 hour: one would need to check how it is done in the TOF cosmics event display and verify if there is a way to make a version compatible with my new GlobalTrack version without major rewrite.
• Fix double-free/segfault at the end of ROOT session/Root Browser (alternating between the two symptoms
• Next TS/Prev TS buttons

Probably of interest to:

• @n.herrmann for the usage with mCBM
• @v.friese for the usage with CBM (set of defaults compiling but untested for now)
• @se.gorbunov as a tool to check effect of L1 changes in mCBM context

Example screenshot: comparison of first event (under trigger derived from typical trigger 4 + TRD + limit on STS counts) in first TS with master L1 tracking and the version from MR !1110 (merged)

• Top: master version, 4 tracks
• bottom: MR 1110 version, 2 tracks

Edit: add redmine Refs #2430