salt-cloud fails to honor 'password' in cloud options before raising an exception

[dkiser]

salt-cloud bootstrap method https://github.com/saltstack/salt/blob/develop/salt/utils/cloud.py#L318 does not honor 'password' or 'win_password' options in the cloud config but explicitly requires them to be set in the context of the vm_. We should fix this so the cloud options are honored if the vm_ doesn't explicitly have a password set, but one is set higher in the deep copy hierarchy.

salt versions:

           Salt: 2015.5.2
         Python: 2.7.5 (default, Jun 17 2014, 18:11:42)
         Jinja2: 2.7.3
       M2Crypto: 0.21.1
 msgpack-python: 0.4.6
   msgpack-pure: Not Installed
       pycrypto: 2.6.1
        libnacl: Not Installed
         PyYAML: 3.11
          ioflo: Not Installed
          PyZMQ: 14.3.1
           RAET: Not Installed
            ZMQ: 3.2.5
           Mako: Not Installed

Will probably throw i a PR on 2015.5 branch for fix as I feel its a bug and use latest develop that includes the win_password to kill 2 birds with one stone.