Fixes a number of bugs introduced by cc61700.  texmanager will now still pass when font.family is a list of strings (though there's no sane way for LaTeX to deal with that, but that's nothing new).
Make weighting by position in the list less magical
Long line
Merge pull request #2012 from mdboom/texmanager-family-list

texmanager doesn't handle list of names for `font.family`