Minor edits to KTDBScan and KTDBScanTrackClustering.
Added copy constructor and operator= for KTProcessedTrackData.
Initial versions of KTDBScanEventClustering and KTMultiTrackEvent. Untested, but compiling.
Converted TTree-writing of KTProcessedTrackData to use a class instead of a struct.
Added Data/Conversions/KTROOTData.hh/cc to hold ROOT versions of data classes.