bin/yum-printbuilddep: Resolve dependencies on non-packages

For example, previously for docbook2X.spec we printed:

   /usr/bin/sgml2xml
   libxslt
   openjade
   perl
   perl(XML::SAX::ParserFactory)
   texinfo

Now we print:

   libxslt
   openjade
   opensp
   perl
   perl-XML-SAX
   texinfo

Also strip off the epoch number, which is separated from the package
name with a colon, e.g., "4:perl".