Add `Clone/CloneDeep` support for `API_AUTO_SERIALIZATION()`

**Issue description:**
Currently, if you wanted to copy an object, you would either use an already presented in the engine serialization mechanism, or would write your own inheritance based `Clone` methods. I am aware that the preferred method of working in situations like this is to have a prefab, but there are legitimate reasons to want to clone an object. Considering that we are already building on fly entire serialization/deserialization, it should not be a problem to simply add a cloning operation by writing to the target obj of the same type instead of the serialize context. Calls to said generation-based could be implemented with the same inheritance-based system in order to support deep copying. Or maybe separate it into two methods - `CloneDeep` would call base-class'es `CloneDeep`'s as well, while `Clone` would only do one level of cloning.