adding policy checks for cinder

Adding cinder policy rules file for policy checks. Implementing
rule checks as well. Some cinder API calls actually hit nova, so
adding those calls as well.

Also a couple of improvements to the Horizon policy engine. First,
now providing the token scope project_id and user_id as targets by
default, unless otherwise specified.  Most service policy rules
check on or both of these.  Second, checking to see if rule exists,
before attempting enforcement.  If the rule does not exist, using
the default rule for that service.  This now matches what the
service policy engines do.

Implements: blueprint block-rbac

Change-Id: Ifef08b8975280f4e621ba8eebec9d405e1e870a2
Merge "adding policy checks for cinder"
Passing stack_id argument to get_data view

Ignoring kwargs causes wrong key generation for
cache (for memoization) and hence, causes repeated call
of function with wrong arguments list.

Change-Id: I85391f30fa81a27496b3399108b4859b2234591e
Closes-Bug: #1268349
Add update method of volume name and description

Change-Id: I19596f1b83b061a47a8784962e6f74f1f43048cf
Closes-Bug: #1264411
Merge "Passing stack_id argument to get_data view"
Merge "Add update method of volume name and description"