Updated lib.cgraph Visual Studio build.
Updated lib.cgraph Visual Studio build.

This build also needs Bison and Flex.

ellson/graphviz,ellson/graphviz,ellson/graphviz,ellson/graphviz,ellson/graphviz,ellson/graphviz,ellson/graphviz,ellson/graphviz,ellson/graphviz,ellson/graphviz,ellson/graphviz