CORE-4095 Added Copy Pipeline support.

Added copyWorkflow method to AppUserServiceFacade interface.
Added copyWorkflow method to AppsViewPresenter that calls the new AppUserServiceFacade method and fires an EditWorkflowEvent on successful response.
Updated AppsViewPresenter::onCopyClicked to call the new copyWorkflow method if the selected App has more than 1 step.
Renamed the AppsViewPresenter::fetchTemplateAndFireEditWorkflowEvent method to fetchWorkflowAndFireEditEvent.
Added some ErrorHandler TODO comments.

Some ErrorHandler posts should include a message to the user in addition to posting exception details.