Patch from  petete.zur88, Issue 580: image.DDS_RGB_DXT1_LOAD (and similar) throw ImageException
Patch from  petete.zur88, Issue 580: image.DDS_RGB_DXT1_LOAD (and similar) throw ImageException

The problem is that the image.codecs.s3tc.PackedImageData doesn't override the
method get_texture inherited from AbstractImage.  Reusing the implementation of
_get_texture to implement get_texture fix the problem.  (There is another bug,
a function in the same module uses the unknow object 'c_ubyte', this can be
solved too using 'ctypes.c_ubyte')

theblacklion/pyglet,oktayacikalin/pyglet,oktayacikalin/pyglet,oktayacikalin/pyglet,oktayacikalin/pyglet,theblacklion/pyglet,theblacklion/pyglet,theblacklion/pyglet,theblacklion/pyglet,oktayacikalin/pyglet