Draft: Resolve "prepare for DetDesc decommissioning"
- add
DetCompat
subdirectory to host all the DetDesc/DD4hep dispatching code - add
DetCompat/ConditionAccessorHolder.h
to replaceDetDesc/GenericConditionAccessorHolder.h
Closes #222
DetCompat
subdirectory to host all the DetDesc/DD4hep dispatching codeDetCompat/ConditionAccessorHolder.h
to replace DetDesc/GenericConditionAccessorHolder.h
Closes #222