- 'delete' is a C++ keyword; use 'del_table' instead
	- apply Py_CHARMASK() to del_table[i] before using it as an index
	  *** this fixes a bug that was just reported on the list ***
	- if the translation didn't make any changes, INCREF and return
	  the original string
	- when del_table is empty or omitted, don't copy the translation
	  table to a table of ints (should be a bit faster)

Rewrote maketrans() to avoid copying the table (2-3% faster).