Adding status field to image location -- DB migration

Adding a status field to image's each location property, each location
status can be 'active', 'pending_delete' and 'deleted'.

Under location's status information Scrubber service can make cleanup
based on DB records also but not a dedicated queue-file for each image.

This is first part of this change which covered DB core migration.

Partially-Implements BP: image-location-status

Change-Id: I013b70d55ef14a3ceaca962f9bc48296cb8b2552
Signed-off-by: Zhi Yan Liu <zhiyanl@cn.ibm.com>
Merge "Adding status field to image location -- DB migration"