Mouths for HTTP(S) and the Util::WWW convenience methods
 LaTeXML::Package basic url-searching for inputs; prohibit loading bindings for remote requests
 urlbase doesn't need to be passed into pathname_find
Merge branch 'wwww-input-enhancement' into www-input-enhancement
 url bookkeeping in the high-level APIs
Merge pull request #4 from dginev/www-input-enhancement

Web input enhancement (addition lf LaTeXML::Util::WWW, accomodations for fetching files via http); Thanks Deyan