Adding NSW Overlay tools (ATLASSIM-4065) (ATLASSIM-4066)

Adding Tools for NSW Overlay. See JIRAs ATLASSIM-4065 & ATLASSIM-4066

This is only the first, crude implementation of NSW Overlay. MM Overlay specifically needs more work in regards to the merging of digits.

RDO to Digit tools are written out for sTGC and MM.

Will add Overlay tests after this MR.

added Digitization MuonSpectrometer Overlay master labels

changed the description

This merge request affects 9 packages:

• Event/EventOverlay/EventOverlayJobTransforms
• MuonSpectrometer/MuonCnv/MuonByteStreamCnvTest
• MuonSpectrometer/MuonCnv/MuonMM_CnvTools
• MuonSpectrometer/MuonCnv/MuonSTGC_CnvTools
• MuonSpectrometer/MuonDigitization/MM_Digitization
• MuonSpectrometer/MuonDigitization/sTGC_Digitization
• MuonSpectrometer/MuonOverlay/MM_Overlay
• MuonSpectrometer/MuonOverlay/MuonTruthOverlay
• MuonSpectrometer/MuonOverlay/STGC_Overlay

Adding @jchapman ,@rosati ,@ahaas ,@tkharlam ,@tadej ,@wleight as watchers

added EDM review-pending-level-1 labels

CI Result SUCCESS

	Athena	AthSimulation
externals
cmake
make
required tests
optional tests

Full details available at NICOS MR-24616-2019-07-04-00-47
AthSimulation: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-CC7 856]