“The taxi cab owners' association come to this court for relief and I think we should give it to them. The writs of prohibition and certiorari lie on behalf of any person who is a ‘person aggrieved’, and that includes any person whose interests may be prejudicially affected by what is taking place. It does not include a mere busybody who is interfering in things which do not concern him; but it includes any person who has a genuine grievance because something has been done or may be done which affects him: see Attorney General of the Gambia v. N'Jie and Maurice v. London County Council. The taxi cab owners' association here have certainly a locus standi to apply for relief.”