ZipperAG-1.0.0: README.md

This source code complements the paper
**Zipper-based Attribute Grammars and their Extensions.** 
Pedro Martins, João Paulo Fernandes and João Saraiva. 
In the *Proceedings of the 17th Brazilian Symposium on Programming Languages (SBLP’13), September 29 - October 4, Brasilia, Brasil. LNCS*