use form layer to bind request data to the model instances

[lsmith77]

see here for an example https://github.com/liip/LiipHelloBundle/blob/master/Controller/RestController.php#L80

this would allow you to leverage the form layer instead of manually doing: https://github.com/dsyph3r/connect/blob/master/src/Connect/ContactBundle/Controller/ContactController.php#L53

furthermore the redirect at the end you can also leave to the rest bundle