Proposal for detector constructor names
=======================================

Detector constructors are identified by a unique name. This name is 
identical to the name of the creating factory object.
This small writeup is a proposal to properly name these factory 
methods in order to avoid nameing clashes.


- Experiment specific detector constructors names have the 
  experiment name as a namespace prefix
  examples: CLIC_<detector>, ILD_<detector>, etc.
- Experiment specific detector constructors reside in 
  experiment specific packages such as ddsim (for ILD).


- Generic DD4hep detectors will have the prefix DD4hep_

__or__   (to be discussed)

- Generic DD4hep detectors will have no prefix
- Generic DD4hep detector constructors reside in the package DDDetectors
  (to be created)


In case a experiment specific detector constructor is sufficiently 
generic that it could be applied in several detector designs and 
hence the visiblility should be upgraded, the detector constructor 
may be imported to DDDetectors.

- Consequently the detector constructor prefix has to change.
- For some time (e.g. 1 year) the old factory may still be 
  supported along with some ugly deprecation printout.