Greek localization

Hello,

Sorry that I forked and did my work on master, in hindsight I should've done this via my own branch instead. Really sorry, I am still new to git and github.

I have made an Addresses, Phone Numbers and Persons providers, and did some small tests which looked OK to me. 

If you need any other info from me, you can contact me on twitter [@georgeharito](http://twitter.com/georgeharito/).

Thanks!

PS. I love this plugin, I use it all the time!