BUG 2302 : odl-clustering-test-app should not be part of the odl-restconf-all feature set

This patch does the following,

1. It removes odl-clustering-test-app from the restconf features
2. Move odl-clustering-test-app to the md-sal feature (just like odl-toaster)
3. Removes all unneccessary dependencies from odl-clustering-test-app
4. Removes all the clustering configuration files from the odl-clustering-test-app feature

This now allows the odl-clustering-test-app to be used with/without clustering. It also
eliminates the problem is inadvertently installing the odl-clustering-test-app when installing
odl-restconf-all.

Change-Id: I8021f88c967576aa8cf8da54dbfa8f4464233bc3
Signed-off-by: Moiz Raja <moraja@cisco.com>
(cherry picked from commit fba140bf09ffbf8694aa41f544caaa331c2ec29a)
Bug-2136 - fix for is-local-path

Change-Id: I38a58683c94c54e9f399df56aa586e3916f75e41
Signed-off-by: Kamal Rameshan <kramesha@cisco.com>
(cherry picked from commit a8477c3af9b6b2de6037404f11e1835ac6c710c2)
Merge "BUG 2302 : odl-clustering-test-app should not be part of the odl-restconf-all feature set" into stable/helium
Merge "Bug-2136 - fix for is-local-path" into stable/helium