Fix for "draw images as texture"

Zooming in on images in Image window now shows pixels again (was filtered).

Now the glaDrawPixelsTex() and glaDrawPixelsAuto() have an argument to 
define if images should zoom in with linear filter, or draw pixels.



git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@55357 954f8c5b-7b00-dc11-b283-0030488c597c