Prebind request was missing from new action template

I couldn't find any references to this issue so I don't know if it was made on purpose but [new action create template](https://github.com/symfony2admingenerator/AdmingeneratorGeneratorBundle/blob/master/Resources/templates/CommonAdmin/NewAction/create.php.twig#L11) was missing [preBindRequest()](https://github.com/symfony2admingenerator/AdmingeneratorGeneratorBundle/blob/master/Resources/templates/CommonAdmin/EditAction/update.php.twig#L16) method.