Draft: add track event and kernel for lamarr
Lamarr requires access to LHCb::Track from Run 2. Take LHCb/run2-patches versions of Kernel/LHCbKernel and Event/TrackEvent, move to Run2_XXXXXX for compilation support, and wrap LHCb::Track as LHCb::Run2::Track to allow simultaneous compilation. Will also allow CellID fix.
Move from !29 (closed) which was horribly out of date.