62X SLHC GEMGeometryBuilder cleanup

* The GEMGeometryBuilder module is duplicate in the code. The correct location is fact in https://github.com/cms-sw/cmssw/tree/CMSSW_6_2_X_SLHC/Geometry/GEMGeometryBuilder/python (not https://github.com/cms-sw/cmssw/tree/CMSSW_6_2_X_SLHC/Geometry/GEMGeometry/python)
* Extended2023HGCal does not have ME0 (https://twiki.cern.ch/twiki/bin/view/CMSPublic/SWGuideUpgradeGeom#Extended2023HGCal)

* Not included suggestion: include GEMGeometryBuilder module in Extended2023TTI 
(https://twiki.cern.ch/twiki/bin/view/CMSPublic/SWGuideUpgradeGeom#Extended2023TTI)

EDIT:
* comp11 is an unused parameter in GEMGeometryBuilder. It is present and used in the RPCGeometryBuilder though. Since the GEMGeometryBuilder package is pretty much a copy-paste of RPCGeometryBuilder, we inherited that param. I deleted it. 
* useDDD is now a tracked parameter.
* GEMGeometryParsFromDD.cc and GEMGeometryParsFromDD.h have never been used (we only need ...FromDDD and ...FromCondDB). Also these files were probably copied straight from the RPC code. I deleted them as well. 
* Finally, I made some aesthetic changes to the ME0GeometryAnalyzer code and configs.