In a hierarchical component, the compositor allowed connections in any
direction between ports of the parent component and inner ports.  It was
possible to not only connect from the output of an inner component to
the output of the parent component, but also in the opposite direction
(which should not be possible).

Inside a parent component, the ports of the parent component should
change their kind. Input ports become output ports and vice versa. With
this change considered, only connections from output to input ports
should be allowed.

Issue-Ref: 3998
Issue-Url: https://af3-developer.fortiss.org/issues/3998


Signed-off-by: Ulrich Schöpp <schoepp@fortiss.org>