change pango version requirement to match the version that seems to work on fc5 and indicate that cairo is required by libpangocairo and only indirectly by graphviz.
change pango version requirement to match the version that seems to work on fc5
and indicate that cairo is required by libpangocairo and only indirectly by graphviz.

ellson/graphviz-web-dynamic,ellson/graphviz-web-dynamic,ellson/graphviz-web-dynamic