Yay! After months, distributed client/core operation is working again!

Yay! After months, distributed client/core operation is working again!
There is still some work left concerning menu states, progress bar, and the dialog,
and also we don't have user management yet (so you have to use user "Default" and
password "password" for both internal and external cores), but basically it's working.
This also (finally!) closes BR #17.