Blender Git Loki

Added Simple Image Background Exporting for Yafray

Add an image texture to the world (in any channel, the first one with an image will be used) and it will be exported as an image background
The texture 'bright' slider is connected to the 'power' variable

If the image selected ends in hdr, it will be exported into an HDRI block.
The texture 'bright' slider effects exposure adjust (it is slider value - 1) so a value of 1 == no expousre adjust. (this needs a better solution in a later implementation)