Add a new method on datastoredriver: getCapabilities, which will be called by liststoragepoolcmd. UI can make decision based on the capabilities of the storage.
And also add a new table: snapshotdetails

Conflicts:
	plugins/storage/volume/default/src/org/apache/cloudstack/storage/datastore/driver/CloudStackPrimaryDataStoreDriverImpl.java
StoragePoolResponse.getId() returns a String with an UUID
Expose getPrimaryDataStore(String uuid) through the DatastoreManager interface so it can be used clients.