CLI Delete and Show grammar extension for collection.

Extends the grammar for the CLI Delete and Show commands to handle
- show field for object collection, and
- delete elements in a sub-collection under a top-level collection.

-Sample CLI inputs:-
**To show the VTEP name**
> vtep management-ip 119.15.112.22 show name

**To delete bindings**
> vtep management-ip 119.15.112.22 delete binding vlan XXX
> vtep management-ip 119.15.112.22 binding delete network-id YYY

Note:
- The above delete commands can delete multiple resources (bindings).

Fix MN-1824