gulp: add `testonly` target - like gulp test but without gulp vet
gulp: add `testonly` target - like gulp test but without gulp vet

to be able to actually run the tests, without jshint & jscs getting in the way

AllenBW/manageiq-ui-service,dtaylor113/manageiq-ui-self_service,AllenBW/manageiq-ui-service,ManageIQ/manageiq-ui-service,ManageIQ/manageiq-ui-service,AllenBW/manageiq-ui-service,ManageIQ/manageiq-ui-self_service,dtaylor113/manageiq-ui-self_service,AllenBW/manageiq-ui-service,ManageIQ/manageiq-ui-self_service,ManageIQ/manageiq-ui-service,ManageIQ/manageiq-ui-self_service,dtaylor113/manageiq-ui-self_service