Do not run git-cloned ksc master tests when local client specified

There is no reason to run both the KSC Master test and a locally
specified keystoneclient. If the local keystoneclient path is set
only use the KcOptTestCase not the KcMasterTestCase.

Change-Id: Ib9a1e06b2e760a97e3318263b85631c436e23141
Closes-bug: #1371428
Merge "Do not run git-cloned ksc master tests when local client specified"