Modified activities_controller#duplicate to avoid some undefined activity error that occurred when a Campaign with activities that were budgeted was being duplicated.
Modified activities_controller#duplicate to avoid some undefined activity error that occurred when a Campaign with activities that were budgeted was being duplicated.

ekylibre/ekylibre,ekylibre/ekylibre,ekylibre/ekylibre,ekylibre/ekylibre,ekylibre/ekylibre