Robotics Service Bus

Currently, if rsb objects are not properly deactivated, the python process does not terminate correctly, even if exit is called. This is caused by hanging background threads from the connectors. While it is usually a good habit to properly deactivate rsb objects, this is not always easily in python, as no automatic destruction mechanism exists. Especially in the case of an exception it is hard to correctly tear down remaining rsb objects bevor passing the exception to the python runtime again for program termination. We should somehow find a way of improving this situation so that processes don't always hang around dangling without clear indication why.