implement Shashlik Calorimeter

athena.xml

compact/ci_ecal.xml

compact/ci_ecal_shashlik.xml

compact/ecal.xml

src/GaseousRICH_geo.cpp

src/GeometryHelpers.cpp

src/GeometryHelpers.h

src/HomogeneousCalorimeter_geo.cpp

src/ShashlikCalorimeter.cpp

src/ce_MRICH.cpp