Reorganize FRLG RNG code

[theastrogoth]

This splits much of the RNG Helper program into separate files to make it easier to add new programs as we go. I made a few tweaks to some other things as well:

• reuse existing structs where possible rather than new ones (will prevent the need to do conversions in a few spots)
• tweaked some names in AdvRng
• added a way to get NatureAdjustments
• added an RNG Manipulation section to the FRLG panels
• Made "hard" resets for RNG manip more reliable
  • previous timings sometimes missed the initial black screen when the game was launched