0.8.14.2:

0.8.14.2:
	Lots of GC cleanups:

	* use N_WORD_BYTES where appropriate, even in gencgc.c
	* use inline functions instead of macros (there are a few cases
	  yet to replace, though)
	* use `fixnump' where possible instead of `& 0x3' (which will
	  break with 64-bit ports)
	* tweak NWORDS to function correctly for n_bits greater than
	  the word size (important for 64-bit ports)
	* changes to use to new, improved NWORDS function when
	  appropriate (e.g. for determining the length of float arrays)

	purify.c needs some of the same tweaks; I have a version which
	  seems to work on alpha64 but fails at the end of warm-init.

	Passes all tests.