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
We could turn these to return ```IEnumerable<string>``` and have only the getter, then we'll use a data member to back this property. For example:

```cs
class NodeModelItem
{
    List<string> returnKeys = new List<string>();

    // Some other stuff...

    public IEnumerable<string> ReturnKeys { get { return this.returnKeys; } }
}
```

Does that make sense? It seems like it will work with ```DataMember``` attribute too.