remove some cruft

Change-Id: If68fccf644099de18bf47fee619992b9094796da
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>
in the scanner, only remove connections the scanner created

Task-number: QBS-394

Change-Id: I4659746be6004042949038450e2015fbb5f70b77
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>