Add QA framework OptionParser options

The options need to be specified here otherwise gitlab-qa treats them as invalid options.

We pass all the options through to the QA framework. This avoids the problem of needing to make sure there's only one -- separator; we pass through all the options, including the separator.

This also makes exe/gitlab-qa redundant with bin/qa so we don't have to maintain duplicate scripts. This is done by moving the code from bin/qa to its own class, which also makes it easier to unit test.