Improve json schema validation for requests left

Implements: bp implement-table-schema-based-validation
Change-Id: I31eafeabb4330fb9f1c7f146f51401e3c360b79b
Merge "Improve json schema validation for requests left"
Add 'last_updated' to 'table_info'

Update table status to *_FAILED if it stucks
to CREATING/DELETING state for a long time

Implements blueprint: table-info-timestamp

Change-Id: I03659858285082e3eca88846bea3c8fb7a3009cf