1.0.4: Merge pull request #5 from GromNaN/patch-1

Fix silex requirements

1.0.3

Add PHP 5.3 to the tests environment

1.0.2: Merge pull request #2 from willdurand/override-formats

Allow to override formats

1.0.1: Merge pull request #1 from willdurand/patch-1

Require stable packages