Added color sat=0 interpolation test.
Added color sat=0 interpolation test.

yyd01245/libavg,hoodie/libavg,yyd01245/libavg,hoodie/libavg,th3infinity/libavg,scotty007/libavg,yyd01245/libavg,libavg/libavg,libavg/libavg,scotty007/libavg,th3infinity/libavg,scotty007/libavg,libavg/libavg,scotty007/libavg,hoodie/libavg,yyd01245/libavg,th3infinity/libavg,th3infinity/libavg,hoodie/libavg,libavg/libavg