Configurable filename rejection for Archive.extract()

Currently Archive.extract() will only extract/create files that use the "safest" filename characters. Add an option to specify a different allowed character set for more relaxed security.

I'm wondering if it might also be useful to have a "blacklist" of filename characters you won't allow (which may be significantly shorter than the list of characters you will allow).

I think a typical blacklist would likely be much longer than a list of characters you would want to allow in filenames since more than half of the 256 possible character values should normally not be used in filenames (e.g. control characters (< 32) and characters > 127).