1.0.28.33: minor post-DEFGLOBAL cleanups

1.0.28.33: minor post-DEFGLOBAL cleanups

 * Call array-accessor dispatch tables %%foo%% instead of **foo** to
   warn off the unwary.

 * Set their size to (1+ widetag-mask) -- this should not really matter
   since we check for other-pointer-lowtag before stripping the widetag,
   as widetag are always immediate objects, so the low bit is zero.
   ...but this is more obviously correct, and costs us, what 4 words
   of storage.

 * Mark one FIXME/KLUDGE more, since people have been so busy getting
   rid of them...

 * Restore the imperative tone in DEFVAR docstring.

 * Oops, left one FLUSHABLE too many in last commit.