fsgs/amiga/roms.py: Add KickRom SHA1 sums from German A500 and A4000

[Yamakuzure]

Before my old Amiga computers died, I ripped the ROMs from them. Unfortunately the machines sold here in Germany seem to have been equipped with older Kick Rom versions then in other parts of the world.

To use both ROMs without any issues (I do not have any other ROM files), I've added them to the roms.py file.

[FrodeSolheim]

I cannot accept the pull request currently, because the launcher right assumes that it will use specific kickstart versions for each model, to make sure that games from the online game database work correctly, and also for netplay.

I definitively see the problem though, and it should be possible to select and use non-standard ROM files in an easier manner (right now you must select them manually on a per-configuration basis). I might have to think about this and find a better way to solve this use case.