Add unit tests for cli.output_parser

This commit adds unit tests for cli.output_parser.

Partially implements bp unit-tests

Change-Id: Ib5d2df61b791e9d76e0897609eb753e7440558ae
Merge "Add unit tests for cli.output_parser"
Merge commit 'refs/changes/65/81565/4' of git://gold.eng.hq.xensource.com/git/github/openstack/tempest into tmpbranch