Fix skip_path logic if path part is empty

This was the case for the image client.

Change-Id: I5568bf6781ad57524c033868c2ab9f2ba4bb566d
Skip test_rescope_token

There are several problems with revocation events in Keystone and
the test is currently failing on postgres. There's several fixes
proposed in Keystone to fix these but until they're merged this
test isn't working.

Change-Id: I9182d542fae0b4a5280dc482300203f84c8f4d8c
Closes-Bug: #1351026
Merge "Fix skip_path logic if path part is empty"