Ignore generated files.
Unify Glyph interface.

Both TrueType and Cff glyphs now use the same class. In addition, both create a path that can be acessed using glyph.path, which gives the raw, unscaled path. This makes future performance improvements possible.
Made glyphIndexToName work again.
Kerning lookup returns null if no value could be found.

This makes it possible to distinguish between "no kerning value found" and a kerning value of 0.
Parse maxp table correctly for TrueType fonts.
Fix parsing bug in "post" version 2.5 code.