Use of RouteAggregator by Task services for waypoint routes

[derekkingston]

Rather than have Task services request waypoints directly from the route planner(s), Task services should instead make a single request to the RouteAggregator and wait for the single response. This greatly simplifies state transition logic for Task services. In addition, proper handling of heterogeneous vehicles is handled by the RouteAggregator and duplicate functionality need not be in each Task service.