In the APMrover2 repository you can find two more files, that we haven't commented yet:
Link to the code: CreateFlags.
A flag word can refer to one or more bits that are used to store a binary value or code that has an assigned meaning, but can refer to uses of other data types.These file includes Flags for, between others, syntax highligthing, arduino syntax...
Link to the code: nocore.inoflog
These file does nothing for now.