Tests for automatic super generation

[Simn]

The only downside is that all optional arguments of Base become mandatory, but there's nothing we can do about it.

[back2dos]

Thanks. I will look into whether this restriction can be lifted. In the meantime, nothing is to stop users to implement constructors themselves ;)

[Simn]

It could to some extent be lifted by reversing the argument order. Currently the constructor expects the parent constructor's arguments first, followed by the child constructor ones. I think that might be a reasonable change.