Enums for TapNoteType, TapNoteSubType, and TapNoteSource

I intend to make additional useful information available on judgments,
such as TapNoteType and TapNoteSubType( for hold judgments ).

I am submitting this part as a separate pull request because it is more
generally applicable to anything TapNote related.
Merge pull request #244 from sigatrev/TapNote-enums

Enums for TapNoteType, TapNoteSubType, and TapNoteSource