PSR-0 coding style

I know this pull request is disruptive and will certainly be refused but I'm really tired of having to deal with bad formatting, indentation with mixed tabs and spaces and so on.

If you accept this, please be aware that all further pull requests may end up conflicting.
An easy way to fix this is to require code to be rebased on upstream/develop by the foreign developper before he asks for a pull requests. Git has all the tools we need at hand for managing this in the best way possible.

I'm open to discussing this further and even taking care of a planning and developer's information if need be.

Cheers !