TinyGo support about vugu

[bradleypeabody]

Required features (not necessarily a complete list):

• Maps - Vugu makes heavy use of maps, need a full implementation of that which supports thousands of entries with reasonable efficiency.

• Reflection - The main places that use reflection are the data hasher (https://github.com/vugu/vugu/blob/master/data-hasher.go) and the code generator for DOM events needs to do things like: reflect.ValueOf(X).MethodByName("Y") (it's possible there could be some compromise on this, e.g. users of TinyGo could be required to implement the DataHash() method on their components if they use a feature that required unsupported reflection from TinyGo, and there might be a way around having to call MethodByName)

• syscall/js - DOM syncing and DOM events heavily rely on this.