Font structure needs name change

[Lars Clausen <lrclause cs uiuc edu>]

To get the list of fonts from X for FreeType, I need to include Xlib.h, but
that defines a Font struct.  I will need to rename the Font structure to
DiaFont.  Stand by for mass renaming.  I wish I had a refactoring editor:)

-Lars

-- 
Lars Clausen (http://shasta.cs.uiuc.edu/~lrclause) | Hårdgrim of Numenor
"I do not agree with a word that you say, but I    | Retainer of Sir Kegg
will defend to the death your right to say it."    |   of Westfield
    --Evelyn Beatrice Hall paraphrasing Voltaire   | Chaos Berserker of Khorne