Add the QCustomPlot widget. Thanks to Emanuel Eichhammer for granting a
license change. Move some common code from ui/gtk/tcp_graph.c to
ui/tap-tcp-stream.[ch]. Get rid of tcp_graph_selected_packet_enabled().
It was only used in the menu code and didn't match what we were doing
elsewhere.
Still quite a bit of work to do but it's a promising start.
svn path=/trunk/; revision=51538