* gdbtypes.h: Create struct rank.
Convert all 'BADNESS' macros to const struct rank declarations.
(sum_ranks): New function.
(compare_ranks): New function.
* valops.c (find_oload_champ): Updated.
(classify_oload_match): Use compare_ranks.
Improved comments.
(compare_parameters): Use compare_ranks.
* gdbtypes.c: Initialize 'BADNESS' constants.
(sum_ranks): New function.
(compare_ranks): New function.
(compare_badness): Use compare_ranks.
(rank_function): Use global constants instead of literals.
(rank_one_type): Ditto.
Return struct rank.
Use sum_ranks.