#144 overloading the text sanitizer

[Kevin Olbrich]

It would be potentially helpful if an installed module
could overload the global text sanitizer function. For
example, a wiki module could overload this function and
do some additional parsing (i.e., detecting wikiwords
and making links to them) either before or after the core
sanitizer is called. This would allow that particular type
of module to detect and make links to the wiki from any
other module that handles text.