* bug fix: CERROR accepts a function as its first argument.
* bug fix: NTH an NTHCDR accept a bignum as index
arguments. (reported by Adam Warner)
+ * optimization: character compare routines now optimize comparing
+ against a constant character. (reported by Gilbert Baumann)
* fixed some bugs revealed by Paul Dietz' test suite:
** LAST and [N]BUTLAST should accept a bignum.