pulled from downstream bzflag.  apply sf patch 2210898 (Fix for some potential FTGL issues) from Matt Handley (applmak) where he adds some asserts that check for the conditions that provoke glTexSubImage2D to return GL_INVALID_VALUE.  this is being provoked by ftgl during Advance when the font size (0-2) is smaller than the hard-coded default font padding size (3).
pulled from downstream bzflag.  apply sf patch 2210898 (Fix for some potential FTGL issues) from Matt Handley (applmak) where he adds some asserts that check for the conditions that provoke glTexSubImage2D to return GL_INVALID_VALUE.  this is being provoked by ftgl during Advance when the font size (0-2) is smaller than the hard-coded default font padding size (3).

git-svn-id: 03108f9e8674d800a1076f283f1c09e74d9b8a45@1202 74be908f-6f43-0410-a0eb-e6a2fe4e4ee7

MichaelMarner/FTGL-OSXFix,MichaelMarner/FTGL-OSXFix,MichaelMarner/FTGL-OSXFix