Fix autoloader.
Fix CLI & related files.
Update composer files.

- Fix license information
- Add dependency on fpoirotte/natives4doxygen for later
- Add dependency on GMP extension for later
- Update dependency on PHP (require >= 5.3.4) for later
- Remove Erebot's repository
Move examples to docs/examples/

Update the rest of the files to reflect that.
Fix license/copyright header.
Update README.

- Integrate license change
- Add badges
- Fix various styles
Add strict typing to encoder & decoder.
Fix unit tests.