crit-bit for golang and its applications (sorted map, IP routing table)

 Crit-bit trees (http://cr.yp.to/critbit.html) in golang and its
 applications.
 .
 This implementation extended to handle the key that contains a null
 character from C implementation (https://github.com/agl/critbit).
 Usage ```go // Create Trie trie := critbitgo.NewTrie()