fix issue94 - Add PHP 5.5 compatibility - replace old sf sfInflector class

PR includes the replacement of sfInflector class (add a new class, update "sfInflector" calls, remove un-use "use" declarations).

Tests succeed (with PHP 5.5 RC2, phpunit 3.8-dev).

cf. [issue 94](https://github.com/chanmix51/Pomm/issues/94)