Finally got rid of the XPACKed core and managed to cross-compile
all core words, which greatly simplifies the bootstrapping process.

Saves us an (ok) indirection and will save us more soon.

This should allow me to simplify LOAD's exit mechanism on block
end.

My mind is getting forthy.

This allows me to reclaim some RAM I hadn't even noticed I
needlessly monopolise.

That INIT thing is unnecessary.

Makes xcomp.fs units shorter.

TODO: implement X['] so that I can remove those XCURRENT patterns.

This leaves space for xcomp-core which is growing.

This allows us to move words like ABORT" to xcomp-core, which is
I think the last roadblock before being able to unify all drivers
into a single xcomp layer.

DO and LOOP now only compile words from stable ABI, which make them
suitable for xcomp. This will greatly simplify driver writing and
allow us to mostly avoid the low/high divide in drivers.

LEAVE is still xcomp-incompatible though.

This make us very very tight for "<0x100" limit for literal words.
Hopefully, we won't need more stuff in that area of the binary...

This makes [entry] much simpler. Also, remove unused LITS word.

Now I struggle to remember why I ever did things they way I did.
There must have been a reason...

The goal is to insert device drivers in between.

That makes it easier to write drivers that can be xcompiled.

On the emulator of course...

Gave more priority to CPU in the emulator because initialization would
otherwise be horrendously slow.

Also, made LIST properly handle full 64-chars lines not ending with
a null or CR. Previously, such a line would be accompanied by its
following line, duplicating that line's output.

This allows us to make DO..LOOP more compact.

This was caused by the removal of signed-ness a long while ago.

I'd like to move this code, along with all recipe contents, to blk/.
It's easier if "emul-related" code is gathered at the same place.

Lines edited with the Block editor end with 0xd and (print) spits
spurious CR when printing those lines.

Also, properly initialize ACC in BROWSE.

And use them in all places they make sense.

With all this recent movements, we had a bit of a fragmentation
issue.