Cleanup - remove LWT control for now

This can be added later as a side-library (hopefully at least)

Signed-off-by: Christoph Höger <christoph.hoeger@tu-berlin.de>
Add a (failing) event loop test

Currently the event-loop does not loop at all (i.e. the
roots are not checked after each effect handling)

Signed-off-by: Christoph Höger <christoph.hoeger@tu-berlin.de>