Reach

1) Implement ComputationResult response with the node data which was changed after execution of RunCancelCommand (values, geometry)
2) Add REST service to retrieve static data (for now it is the list of Node Models)
3) Update models drawing logic to avoid Dynamo crash on subsequent client updates
The following ```RenderComplete``` event is being subscribed to multiple times, and there's only one ```VisualizationManager```, even though we know we are unsubscribing from it in ```ModifiedNodesData``` method, if ever there is a case ```RenderComplete``` event does not occur, we end up with a leaking reference to this ```MessageHandler``` object. Of course we can always argue that with a better design (e.g. restructure ```MessageHandler``` in a way that it exists under ```DynamoController``` as class member, and subscribe to the event only once), but having an explicit ```callback``` mechanism here will serve the purpose better. For now this works, but there are other works that will take place to make this scenario easier, we can restructure ```MessageHandler``` when that happens, let's leave this as it is for now.