Quotas by Volume Type

The VolumeTypeQuotaEngine creates a volume, snapshot, and gigabyte
quota for each volume type that exists, in addition to the existing
global quotas for each. These are queried every time a quota operation
happens.

The resources for creating quotas are named: volumes_<vtype>,
gigabytes_<vtype>, and snapshots_<vtype>.

Another patch will have changes to cinderclient for setting project
quotas by volume type.

blueprint quotas-limits-by-voltype
DocImpact

Change-Id: I88261676edcd6eb5b7cea40654a931f32c00815c