Made some stuff from oz80.bas private
* I mostly threw away the old `ASCII` enum and reworked the `OZ80_SYNTAX` enum to use the UCS2 enum from 'bluString'
* `OZ80_MASK` is an opcode handling specific enum, so was moved into the Assembler
* We're now targeting the Sonic 1 disassembly and will implement things as the assembler runs into them