Fix bug when getting `cwl_workflow` in `BioWardrobePluginJobDispatcher` and `BioWardrobePluginJobGatherer`
After update of `cwl-airflow-parser`, `CWLDAG` doesn't have attribute `cwl_workflow` anymore. Now it should be taken as `self.dag.default_args["cwl_workflow"]`
1.1.1
1.1.0
Uses latest: cwl-airflow-parser (at the moment of release it's 1.0.20180918220755) cwltool (at the moment of release it's 1.0.20180912090223) apache-airflow (at the moment of release it's 1.10.0)