The previous name for this was rather misleading. It isn't an actual
jump like you'd expect the `jp` instruction to behave as. Instead, it
behaves more like a `farcall`.
This also makes it consistent with its current command ID name of
`TX_FAR`.
Cleaned up `engine/routines`, in favor of moving files into more
appropriate directories. predef-related routines are now in top-level
`engine`.
`rtc/delete_save_change_clock.asm` has been split into both
`menus/delete_save.asm` and `rtc/reset_password.asm`.
Made a new subdirectory:
* engine/math: Contains all generic math-related routines.
