Created Issue: Set MaxDataServiceVersion to 3.0 in model builder [707]

If we don't do that, client code won't work for V3 features like collection property.

A workaround right now is to use following code:
var model = mb.GetEdmModel();
model.SetMaxDataServiceVersion(Version.Parse("3.0"));

We should set this value to 3.0 as default. With 3.0, all 2.0 and 1.0 can still work.