Fix: Fix PHP-CS-Fixer to a working version

[localheinz]

Follows #6172 (comment).

Unfortunately a change I proposed in fabpot/php-cs-fixer results in failing builds on Travis.

See https://github.com/fabpot/PHP-CS-Fixer/pull/342.

[localheinz]

/cc @samsonasik @Ocramius @weierophinney

[localheinz]

As posted in #6172 (comment):

Another alternative would be to update .travis.yml:

script:
  - vendor/bin/php-cs-fixer fix --config-file=.php_cs -v --dry-run ./library

[localheinz]

In my opinion, though, yet another alternative would be allow the path argument to be optional, since the paths are defined in the configuration in .php_cs anyway.

This would probably be the cleanest solution.

[samsonasik]

@localheinz I applied your suggestion about updating .travis.yml on #6172 ...

[localheinz]

@samsonasik

It's very likely that all of the PRs that have been building since fabpot/PHP-CS-Fixer@288b3ce will need to have this change as well.

[samsonasik]

👍

[localheinz]

@Maks3w

I'm working on making the path argument optional since

$ vendor/bin/php-cs-fixer fix --config-file=.php_cs -v --dry-run .

in combination with .php_cs (as it is) is only providing . as path argument because it's non-optional (I believe).

[Maks3w]

Thank you @localheinz