Added "misc-fixed" as a fallback font to handle locales where

Added "misc-fixed" as a fallback font to handle locales where
adobe-helvetica does not have all the required characters.  The fixed
font is ugly but does have a rather complete set of characters, while
the helvetica font is missing Cyrillic characters (at least on my
distro).  I haven't found a way to get a nicer font that includes
Cyrillic to work with XCreateFontSet, but I don't fully understand
why.  I'll try to improve things further in the future if I figure out
what's all going wrong.

In the process I had to rewrite the code to insert the pixel size into
a font name (replacing a "*" in that field).  The new code is much
more general.