add ReadmeTest
minor #508 add ReadmeTest (keradus)

This PR was squashed before being merged into the 1.0.x-dev branch (closes #508).

Discussion
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add ReadmeTest

Test checks if readme file is up to date.

This will make Travis failed if sb forgot to regenerate readme at PR.

Commits
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ce3cd32 add ReadmeTest
Merge branch 'master' of git://github.com/fabpot/PHP-CS-Fixer