This adds a new configration file for fonts with several more features,
most notably the ability to specify numeric weights for fonts in a
family, and specify aliases for weights. This will help help choose an
appropriate font for a "bold" weight request, rather than just applying
auto-bolding.
Bug: 14538154
Change-Id: Ib4d54d66a0c68b7d46e665d7cd94e97b72468e95
Also parse fallback_fonts.
This lets layoutlib automatically use the same fonts as the base
platforms, for instance it now uses the new ICS fonts.
Change-Id: Id6e778dc0e3f2a9112601e0eaf8499a9713ec433
