applying the more sophisticated binary GCD. (thanks to Juho
Snellman)
* optimization: COUNT on bitvectors now operates word-at-a-time.
+ * optimization: ASH with a positive, but not necessarily constant,
+ (leftwards) shift, when in a modular context, is compiled to a
+ hardware shift.
* fixed some bugs revealed by Paul Dietz' test suite:
** FORMAT variable parameters ("~V<char>") are defaulted properly
if the corresponding argument is NIL.