removed privileged option on container creation

the privilege option is not present in Docker-py code so this ansible module is not working anymore.

FYI, in docker-py, as of version 0.3.2 : 
```
    def create_container(self, image, command=None, hostname=None, user=None,
                         detach=False, stdin_open=False, tty=False,
                         mem_limit=0, ports=None, environment=None, dns=None,
                         volumes=None, volumes_from=None,
                         network_disabled=False, name=None, entrypoint=None,
                         cpu_shares=None, working_dir=None, domainname=None,
                         memswap_limit=0):
```