Resolve API import issues (quantum)

Restore the imports in the api init file, without including the "from"
to ensure api calls still must specify "api.nova", "api.quantum", etc.

Fixes bug #1125632

Change-Id: I981105ce0ed7f1352de42fe2c0620665ba378823
Added encryption support for volumes

The modifications are to the volumes/cinder area of the dashboard. In
the cinder client's API, we exposed the metadata parameter in the
"create" method, and then added a choice field to the create form to
(optionally) select an encryption mode.  The user's selection is then
passed in to cinder as volume metadata.  We also modified the detailed
volume view to display all metadata associated with a volume.  We also
added a flag in OPENSTACK_HYPERVISOR_FEATURES to enable/disable the
encryption field.  Finally, we added a test case to exercise the
encryption choice field.

The following changes were made to Nova to support this feature:

Added support to encrypt volumes. Modified the libvirt driver to
encrypt volumes during the attach call. Created a new VolumeEncryptor
class that is responsible for encrypting volumes. The default
implementation does not do enryption, and a DmCryptVolumeEncryptor is
provided to encrypt volumes using dmcrypt.

Added a new KeyManager interface. The KeyManager is used by the
VolumeEncryptor to retrieve the key necessary for encryption.

Change-Id: Idb6a923f0e3fa52ca800ebd621e247d972b7c714
Implements: blueprint volume-encryption-field
Merge "Added encryption support for volumes"