A list of families is returned. Each variant contains the variant's
style, the filepath for the variant, and the index of the variant in the
file. This info should be enough to get freetype to actually load a
font.
This function isn't exactly useful, but it's working ffi with the
fontconfig library. Woo! Next step will be returning some objects with
more information (like font path so we can start rendering glyphs!).
