Merged requested to merge jojungge/athena:CSC_DigitToId into master
this is a thorough clean-up of the
CscDigitizer which is needed to make !49749 (merged) run.
- Use offline Identifiers to retrieve the CscReadOutElements from the detector manager
- Useage of modern c++ std::arrays where possible and needed
- Proper indentiation in the second commit