cloneEx method
Creates an obj
clone.
If deep
is true it will perform a deep/recursive set
(i.e. clones filed values in case they are clonable objects)
Implementation
T cloneEx(ClonableEx obj, {dynamic exParam, bool deep = false}) =>
((createEx(fields.valueMap, exParam) as ClonableMixin)
..setMap(fields._map, deep: deep)) as T;