refactor for tag and suite importing in CaseImporter, where applicable
refactor for tag and suite importing in CaseImporter, where applicable

mozilla/moztrap,mccarrmb/moztrap,shinglyu/moztrap,mozilla/moztrap,shinglyu/moztrap,mccarrmb/moztrap,bobsilverberg/moztrap,shinglyu/moztrap,shinglyu/moztrap,mozilla/moztrap,bobsilverberg/moztrap,mozilla/moztrap,bobsilverberg/moztrap,mccarrmb/moztrap,mccarrmb/moztrap,mozilla/moztrap,shinglyu/moztrap,bobsilverberg/moztrap,mccarrmb/moztrap