Bug 582 - added tag param to run command

Fixed bug #582: https://bugs.tddium.com/bugzilla/show_bug.cgi?id=582

Now you can run tests from CLI with tag param: ```tddium run --tag='Some tag for session'``` - tag param will be added to session.
Another part of task, for showing tag in report header, located here: https://github.com/solanolabs/tddium_site/pull/505