minor #861 Reorder wording (thewilkybarkid)

This PR was merged into the master branch.

Discussion
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Reorder wording

Quick reordering of the words in a docblock (not sure an interface can implement a service provider 😃).

Commits
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861de4ea Reorder wording

src/Silex/ServiceProviderInterface.php

@@ -12,7 +12,7 @@
 namespace Silex;
 
 /**
- * Interface that must implement all Silex service providers.
+ * Interface that all Silex service providers must implement.
  *
  * @author Fabien Potencier <fabien@symfony.com>
  */