Support for Patch across multiple data nodes

- Added new method updateMultipleDataLeaves to perform Update on
  multiple data nodes
- Deprecated singular method of update data node(updateDataLeaves)
- Refactored code where singular version was used
- Updated release notes

Issue-ID: CPS-1006
Signed-off-by: <as00745003@techmahindra.com>
Change-Id: If67280e2dd3ad566de9a8217489f168415e624bc
11 files changed