Removed an invalid sanity check within GafferImage::ImagePlug.
Removed an invalid sanity check within GafferImage::ImagePlug.

chippey/gaffer,andrewkaufman/gaffer,johnhaddon/gaffer,lucienfostier/gaffer,boberfly/gaffer,paulondc/gaffer,GafferHQ/gaffer,hradec/gaffer,cedriclaunay/gaffer,paulondc/gaffer,ImageEngine/gaffer,lucienfostier/gaffer,appleseedhq/gaffer,boberfly/gaffer,GafferHQ/gaffer,cedriclaunay/gaffer,goddardl/gaffer,ImageEngine/gaffer,GafferHQ/gaffer,davidsminor/gaffer,hradec/gaffer,appleseedhq/gaffer,davidsminor/gaffer,hradec/gaffer,andrewkaufman/gaffer,appleseedhq/gaffer,andrewkaufman/gaffer,chippey/gaffer,chippey/gaffer,cedriclaunay/gaffer,GafferHQ/gaffer,andrewkaufman/gaffer,goddardl/gaffer,goddardl/gaffer,davidsminor/gaffer,goddardl/gaffer,hradec/gaffer,boberfly/gaffer,hradec/gaffer,ImageEngine/gaffer,ivanimanishi/gaffer,andrewkaufman/gaffer,paulondc/gaffer,chippey/gaffer,lucienfostier/gaffer,boberfly/gaffer,johnhaddon/gaffer,johnhaddon/gaffer,GafferHQ/gaffer,appleseedhq/gaffer,paulondc/gaffer,lucienfostier/gaffer,ImageEngine/gaffer,davidsminor/gaffer,johnhaddon/gaffer,ivanimanishi/gaffer,cedriclaunay/gaffer,johnhaddon/gaffer,ivanimanishi/gaffer,ivanimanishi/gaffer