Fix bug with cgraph and flat edges. In cgraph, the same edge can have two addresses, depending on whether it is an out or in edge. Make sure to canonicalize.
Fix bug with cgraph and flat edges. In cgraph, the same edge can have
two addresses, depending on whether it is an out or in edge. Make sure
to canonicalize.

tkelman/graphviz,pixelglow/graphviz,MjAbuz/graphviz,kbrock/graphviz,BMJHayward/graphviz,tkelman/graphviz,jho1965us/graphviz,jho1965us/graphviz,tkelman/graphviz,pixelglow/graphviz,pixelglow/graphviz,jho1965us/graphviz,pixelglow/graphviz,MjAbuz/graphviz,kbrock/graphviz,ellson/graphviz,jho1965us/graphviz,pixelglow/graphviz,BMJHayward/graphviz,ellson/graphviz,pixelglow/graphviz,BMJHayward/graphviz,kbrock/graphviz,tkelman/graphviz,MjAbuz/graphviz,BMJHayward/graphviz,jho1965us/graphviz,ellson/graphviz,kbrock/graphviz,ellson/graphviz,tkelman/graphviz,MjAbuz/graphviz,ellson/graphviz,MjAbuz/graphviz,kbrock/graphviz,BMJHayward/graphviz,kbrock/graphviz,jho1965us/graphviz,kbrock/graphviz,tkelman/graphviz,jho1965us/graphviz,MjAbuz/graphviz,BMJHayward/graphviz,kbrock/graphviz,BMJHayward/graphviz,pixelglow/graphviz,ellson/graphviz,ellson/graphviz,MjAbuz/graphviz,jho1965us/graphviz,ellson/graphviz,BMJHayward/graphviz,BMJHayward/graphviz,pixelglow/graphviz,tkelman/graphviz,kbrock/graphviz,pixelglow/graphviz,ellson/graphviz,tkelman/graphviz,MjAbuz/graphviz,MjAbuz/graphviz,BMJHayward/graphviz,tkelman/graphviz,MjAbuz/graphviz,pixelglow/graphviz,tkelman/graphviz,BMJHayward/graphviz,kbrock/graphviz,kbrock/graphviz,tkelman/graphviz,ellson/graphviz,jho1965us/graphviz,jho1965us/graphviz,jho1965us/graphviz,ellson/graphviz,MjAbuz/graphviz,pixelglow/graphviz