Add `goraph`

README.md

@@ -320,6 +320,7 @@ Please take a quick gander at the [contribution guidelines](https://github.com/a
 * [go-gt](https://code.google.com/p/go-gt/) - Graph theory algorithms written in "Go" language
 * [go.matrix](https://github.com/skelterjohn/go.matrix) - linear algebra for go
 * [gostat](https://code.google.com/p/gostat/) - A statistics library for the go language
+* [goraph](https://github.com/gyuho/goraph) - A pure Go graph theory library(data structure, algorith visualization)
 * [mudlark-go](https://code.google.com/p/mudlark-go-pkgs/) - A collection of packages providing (hopefully) useful code for use in software using Google's Go programming language.
 * [plotinum](https://code.google.com/p/plotinum/) - Plotinum provides an API for building and drawing plots in Go.
 * [streamtools](https://github.com/nytlabs/streamtools) - general purpose, graphical tool for dealing with streams of data.