[Feature Request] Vanilla / 0CC / Dn compatibility modes

[Gumball2415]

As the driver and tracker have been modified by at least 3 or more developers at this point, the behavior of some things may have changed over time.

Subtle things for instance, Cxx commands taking effect on the next pattern row (0CC/Dn) instead of immediately (vanilla).

Would it be reasonable to implement behavior compatibility flags for these main versions, once feature parity is reached?

[zeta0134]

In the short term, my primary interest is reaching compatibility with Dn-FamiTracker. I'm not especially interested in chasing behavior in historical forks; rather, my goal is to reach feature parity, document the current state, cleanup the export format to not be a bag of magic numbers... and then start considering changes to that format.

Until it's at feature parity, bhop can be considered unstable and I'm not going to try to promise or maintain backwards compatibility with itself or any older version of FT. One thing at a time.