Implement CopyTex(Sub)Image2D

TRAC #11474

Signed-off-by: Shannon Woods
Signed-off-by: Daniel Koch

Author:    Andrew Lewycky

git-svn-id: https://angleproject.googlecode.com/svn/trunk@132 736b8ea6-26fd-11df-bfd4-992fa37f6226
9 files changed