Better deal with case where two tables have same offset (overlapping tables)
Case font: Aetherfox (kern is zero length; has same offset as maxp)
Handle zero length tables better + maxp fixes.

If maxp table is missing, calculate numGlyphs based on the length of the loca table.
Case font: ??? Used Aetherfox with maxp table missing (old comparator)
Allow subsetter to work if maxp table is missing
Fix bug in data type of maxp version number (fixed, not ushort).