BuildRequires for texlive stuff for F18 and beyond

[Jonathan Underwood]

Hi Jindrich (again),

Perhaps a pragmatic route would be to add a few more virtual provides
to help package maintainers.

tex(latex-base) which would do exactly what tex(latex) currently does

tex(latex) which would pull in texlive-collection-latexrecommended

tex(latex-recommended) which would pull in
texlive-collection-latexrecommended and
texlive-collection-fontsrecommended

tex(latex-extra) which would pull in texlive-collection-latexextra and
texlive-collection-fontsextra

Jonathan.