1.21: Adding more Z80 opcodes, part 7
1.22: Adding more Z80 opcodes, part 8
1.23: Adding more Z80 opcodes, part 9
1.24: Change default framerate
1.25:

- optimized LD rr,dd
- optimized LD (HL),dd
- sorted OPCODE.INC file
- added RL (II+dd)
- added ADD II,rrw
- fixed timings of instructions on OPCODE.INC
1.26:

- fixed timings of instructions in Z80??.ASM
- added synchronization at interrupt-level
1.27:

- changed the memory model to 8k banks instead of 16k banks
- now the bank switch is also done on the "slot" variable,
  this way you can change the banks to another slot and then
  back, preserving the megarom bank selectors. With this change
  F1 Spirit now run.
- changed interrupt emulation, now MSX timing has higher priority
  than PC timing. This will slow down emulation on slower machines,
  but it can prevent deadlocks. As a side effect, Nemesis run on
  correct speed.
- added LD SP,IY instruction
1.28:

- new unificated "emulate" pipeline
- msxvram is now allocated in real time, it reduces the executable size
  and will make life easier when I'll implement msx2 emulation
- fixed timing of automatic opcodes
- RETI does not enable interrupts now, because of this megarom games
  doesn't lock anymore