Cleanup package imports

Cleanup package imports

This removes Import-Package instructions, relying on bundle plugin to
figure them out.

We rework the rib-mock API contract to not rely on static contructor, to
fix one of the failures.

We are removing test-tool bundle integration tests, as these should be
switched to jars.

Change-Id: Ia2ed528ae3d10975e6b99b88414e1b982b70804b
Signed-off-by: Robert Varga <rovarga@cisco.com>