Add a vm_directory field to Dynamips / VPCS / IOU

Fix #246

gns3server/modules/vpcs/vpcs_vm.py

@@ -109,6 +109,7 @@ class VPCSVM(BaseVM):
 
         return {"name": self.name,
                 "vm_id": self.id,
+                "vm_directory": self.working_dir,
                 "status": self.status,
                 "console": self._console,
                 "project_id": self.project.id,