[TASK] Add the phpcs configuration

[sseidelmann]

Adding the php-cs-fixer with PSR2 styleguide
To let it run:

vendor/bin/php-cs-fixer fix
vendor/bin/php-cs-fixer fix --dry-run

I also fixed two files that are not PSR2 formatted.

It would be nice to insert this into travis:

script:
  - vendor/bin/php-cs-fixer fix --config=.php_cs --verbose --diff --dry-run

[jeanmonod]

Have you see the builds? There is an issue with the composer dependencies...

[acrobat]

I'm 👎 on adding this to composer. Imo php-cs-fixer should be installed locally, but this won't enforce the correct use of code style. So maybe it's an option to use a service like styleci.io which will check each pr and report issues with coding style (and provide a patch file)

[sseidelmann]

@jeanmonod jeah, correct. I will check this later.

[sseidelmann]

@acrobat Can be closed maybe. See the new PR #125 for the styleci integration