(MESS) fixed regression in a few MD cart types. nw.
namcos23: Fix 3D computations in timecrs2 [O. Galibert]
Fix memory leak visible apollo driver (nw)
modernized apollo a little bit more (nw)
forgot to remove these (nw)
(MESS) this was not needed anymore after rev22034. I think 
MCFG_NVRAM_HANDLER_CLEAR is now unused and can
be removed.
namcos23: Better understanding of the command format, downhill and 500gp now show something (completely wrong) [O. Galibert]
modernized access for legacy floppy, quite straight forward thing (nw)
Getting rid of token usage in devices (nw)
can hide internally used classes (nw)
upd7220: devcb2 and delegates. (nw)
i8275x: devcb2 cleanup. (nw)
i8275x: Cleanup. (nw)
i8275x: Cleanup. (nw)
no handler usage is possible in devcb so removing not used code (nw)
added assert to src/emu/cpu/i86/i86.c for known index out-of-bounds access (nw)
converted legacy handlers to modern (nw)
lh5810_device: converted to devcb2 (nw)
moved some static variables into state (nw)
removed legacy handler from snes (nw)