Standardize handling of glyph names for U. F. O. output.

This adds a standards-compliant name mangler and a hash table look-up for glyph names (so that we can iterate names that collide after mangling).

Well that's odd. When I run bootstrap, it creates .gitmodules and puts gnulib in there. I'm on Ubuntu 12.04. I do not have gnulib installed. What's your configuration?