make PUT and DELETE idempotent
make PUT and DELETE idempotent

gimler/symfony-rest-edition,alihalabyah/symfony-rest-edition,underq/symfony-rest-edition-experiment,gimler/symfony-rest-edition,locastic/psc-symfony-angularjs,alihalabyah/symfony-rest-edition,den2134/itdTest,den2134/itdTest,beyondkeysystem/psc-symfony-angularjs,beyondkeysystem/psc-symfony-angularjs