Add --no-delete to indexing
Add --no-delete to indexing

To support cases where it's desirable to index without deleting data
and mapping, add a --no-delete option to 'index sync'.

Change-Id: I54973ee69864963878021d376b24bca49caa9570
Partial-Bug: #1491085

openstack/searchlight,openstack/searchlight,openstack/searchlight