Check for installed cinder in filter tests.

Some of the filter tests require that the cinder pkg is
installed on the system, specifically cinder.egg-info/entry_points.

This change check that the egg-info directory exists in the root
cinder directory and determines whether to skip or not.

Change-Id: I36145f170e802aed5dfae8eec4684e60ad3d6f2c
Merge "Check for installed cinder in filter tests."