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
I don't see how an ```ExecuteNode``` class should be a nested class of ```RunCancelCommand```, it needs to be moved out. With what I see from the look of things, it belongs somewhere ```WebServer``` belongs, since it represents the result of computation. It might not be perfect to be alongside ```WebServer```, but it's definitely better than being here.