Refactor integration tests

Refactor integration tests

This patch cleans and adds functionality to the Southbound integration tests.
Specifically, the changes do the following:
1) enable negative test cases that were previously disabled
2) remove checkErased tests, as the configurations aren't replaced but merged
3) consolidate existing Termination Point Interface other_configs testing with
   new update test cases, resulting in full CRUD tests.

Change-Id: I7eff55e452372d16cbaecb125d4a134a690b7c49
Signed-off-by: Ryan Goulding <ryandgoulding@gmail.com>