restapi: Rest API for brick advanced details

Brick advanced details are retrieved if
All-Content is set to true in the header for urls -
/api/clusters/{id}/glustervolumes/{id}/bricks/{id}
and /api/clusters/{id}/glustervolumes/{id}/bricks/
Brick memory statistics information is added under
/api/clusters/{id}/glustervolumes/{id}/bricks/{id}/statistics

Refactored BackendGluster*Resources' addParent method to avoid
calling VdcQuery as only ID is required.

Updated statistics and All-Content header value
in rsdl metadata file.

Change-Id: Ie219c7cf59fec8a21a54f34959ee5966eed7d524
Signed-off-by: Sahina Bose <sahina@gmail.com>