Adding a couple of useful methods:
Adding a couple of useful methods:

- render font.Label to texture using FBO (can't implement using AUX-and-copy
  'cos I can't seem to get that working here)
- calculate width of slice of font.Label

--HG--
extra : convert_revision : svn%3A14d46d22-621c-0410-bb3d-6f67920f7d95/trunk%40844

infowantstobeseen/pyglet-darwincore,infowantstobeseen/pyglet-darwincore,infowantstobeseen/pyglet-darwincore,infowantstobeseen/pyglet-darwincore,infowantstobeseen/pyglet-darwincore