Added I8 support to image node.
Added I8 support to image node.

svn path=/branches/tracking/; revision=1727

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