Fixed ParamRole.objects.get_param_role wrong use in gas manager.
Fixed ParamRole.objects.get_param_role wrong use in gas manager.

By passing params as non keyword arguments, the following exception was given:

TypeError: get_param_roles() takes exactly 2 arguments (x given)

feroda/gasistafelice,matteo88/gasistafelice,OrlyMar/gasistafelice,michelesr/gasistafelice,befair/gasistafelice,feroda/gasistafelice,michelesr/gasistafelice,matteo88/gasistafelice,kobe25/gasistafelice,OrlyMar/gasistafelice,OrlyMar/gasistafelice,michelesr/gasistafelice,kobe25/gasistafelice,kobe25/gasistafelice,matteo88/gasistafelice,matteo88/gasistafelice,feroda/gasistafelice,kobe25/gasistafelice,befair/gasistafelice,befair/gasistafelice,michelesr/gasistafelice,befair/gasistafelice,feroda/gasistafelice,OrlyMar/gasistafelice