PSR + docs

* I changed everything to comply with PSR-2 standard
* I added PHPDocs to methods and attributes
* I've imported Wiki pages into the `docs` dir
* I've translated documentation to Brazilian Portuguese

As it breaks the API you may consider tagging as a new version.
It'd be nice to get this added back in unless there's a particular reason it was removed? It looks like the latest changes are passing :+1: