100% coverage in functional tests

In Rally, we have functional tests that run different CLI
commands and check that the CLI output contains all the expected
data.

We need to ensure that every single subcommand of “rally task”,
“rally deployment” etc. (for example, “rally task start”, “rally
task report”) is covered in these functional test with all possible
parameters usage (e.g. the “--deployment” parameter in “rally task
start --deployment <name>” didn’t get tested, which has lead to
errors recently).

Change-Id: I654ad4317b2d061dd899f5fdfb028cda50af9b8b
Merge "100% coverage in functional tests"