added Slugify package (alternative)

README.md

@@ -583,6 +583,7 @@ Join us on IRC at **#awesome-go** on freenode [web access](http://webchat.freeno
     * [go-runewidth](https://github.com/mattn/go-runewidth) - Functions to get fixed width of the character or string.
     * [guesslanguage](https://github.com/endeveit/guesslanguage) - Functions to determine the natural language of a unicode text.
     * [slug](https://github.com/gosimple/slug) - URL-friendly slugify with multiple languages support.
+    * [Slugify](https://github.com/avelino/slugify) - A Go slugify application that handles string.
     * [toml](https://github.com/BurntSushi/toml) - TOML configuration format (encoder/decoder with reflection).
 * Utility
     * [gotabulate](https://github.com/bndr/gotabulate) - Easily pretty-print your tabular data with Go.