Adds saver for results from `rally verify`

Better integration with tempest can be achieved by analyzing output
of testr. This patch provides parsing testr output and saves results
into database.

Blueprint tempest-verification
Closes-Bug: #1302475

Change-Id: I110bc115bd597df54499ac295d836a87411c4c80
Adds commands for verification results

Command `rally verify list` displays list of verifications
Command `rally verify results` prints raw tests results
Command `rally verify show` prints verification results.
Command `rally verify detailed` prints verification results
with traceback of failed tests.

Blueprint tempest-verification

Change-Id: I19991219c2f184c5158fecc0d234c7a40031e092
Merge "Adds saver for results from `rally verify`"
Merge "Adds commands for verification results"