Add support for Chill bitstring literals (e.h. H'FF00').

	Add support for Chill bitstring literals (e.h. H'FF00').
	* ch-exp.y (match_bitstring_literal):  Fix for proper endianness.
	* expprint.c (print_subexp):  Don't call error on OP_BITSTRING,
	just print B'<unimlemented>'.
	* gdbtypes.c (create_set_type):  Fix bug in length calculation.
	* valops.c, value.h (value_bitstring):  New function.
	* eval.c (evaluate_subexp):  Implement support for OP_BITSTRING.

	* ch-typeprint.c (chill_type_print_base): For TYPE_CODE_FUNC,
	check that return type is non-void, and print in proper Chill syntax.