rose suite-hook: update `cylc stop` syntax

See cylc/cylc#739.
rose test-battery: new cylc shutdown syntax

See cylc/cylc#739
Merge pull request #991 from matthewrmshin/cylc-739

rose suite-hook: update `cylc stop` syntax
rose test-battery: remove debug statements
Merge pull request #995 from matthewrmshin/remove-t-debug

rose test-battery: remove debug statements