Support reading RGB float DDS images
Support reading RGB float DDS images

The DDS plugin is not able to load floating point RGB images saved out by itself. There doesn't appear to be a fourcc code for RGB float/half-float data, so I added the appropriate entries to the RGBFormat table so the images can be loaded properly.
scrawl/osg,openscenegraph/osg,openscenegraph/osg,openscenegraph/osg,scrawl/osg,scrawl/osg,scrawl/osg,openscenegraph/osg