BESTMATCH ignoring user-specified costs

[M0rtenB]

It seems that even when BESTMATCH is specified, the fuzzy matching engine doesn't account for user-specified costs in choosing the optimal match. Consider the following examples:

In [1]: regex.search(r'(voices){1i+1d+2s<=2}', 'voixes voicees', regex.BESTMATCH)
Out[1]: <regex.Match object; span=(0, 6), match='voixes', fuzzy_counts=(1, 0, 0)>

In [2]: regex.search(r'(voices){1i+1d+2s<=1}', 'voixes voicees', regex.BESTMATCH)
Out[2]: <regex.Match object; span=(7, 14), match='voicees', fuzzy_counts=(0, 1, 0)>

Even if the cost is allowed to exceed 1, as in the first search, the engine should still match "voicees", as an insertion of an extra "e" is less of a cost than replacing "c" with "x".

A natural extension would be to allow regex.search(r'(voices){1i+1d+2s}', 'voixes voicees', regex.BESTMATCH), i.e. find the best match with no limit, using costs.