When user changes Workspace for Milestone, all tasks belonging to Milestone are also changed to new Workspace. There should be option to allow user to choose if he wants al tasks to be changed, or just tasks that are in the same Workspace as Milestone, or none.
This is needed to be consistent with possibility that Task may be set to different Workspace than Milestone it belongs to.
As it is now, when workspace is changed for Milestone, all tasks are changed too, overwriting previous state without any warning.
