optimize_graph_df():  - when a mode_T node is enqueued, enqueue it's Projs. This    is needed because most optimizations run on the Proj
optimize_graph_df():
 - when a mode_T node is enqueued, enqueue it's Projs. This
   is needed because most optimizations run on the Proj

[r8251]

killbug2004/libfirm,killbug2004/libfirm,MatzeB/libfirm,davidgiven/libfirm,jonashaag/libfirm,davidgiven/libfirm,MatzeB/libfirm,libfirm/libfirm,8l/libfirm,davidgiven/libfirm,libfirm/libfirm,MatzeB/libfirm,killbug2004/libfirm,davidgiven/libfirm,libfirm/libfirm,8l/libfirm,killbug2004/libfirm,8l/libfirm,killbug2004/libfirm,killbug2004/libfirm,8l/libfirm,MatzeB/libfirm,jonashaag/libfirm,jonashaag/libfirm,davidgiven/libfirm,MatzeB/libfirm,jonashaag/libfirm,libfirm/libfirm,killbug2004/libfirm,libfirm/libfirm,jonashaag/libfirm,davidgiven/libfirm,jonashaag/libfirm,davidgiven/libfirm,8l/libfirm,8l/libfirm,MatzeB/libfirm,8l/libfirm,MatzeB/libfirm,jonashaag/libfirm