GH-18 Reposition dst netLabel on item name change
Revert "GH-18 Reposition dst netLabel on item name change"

This reverts commit c98bb89fa4c375dedb2766a841a0587175287702.
Revert "Revert "GH-18 Reposition dst netLabel on item name change""

This reverts commit e99de77e9ce45bcca939e89726afc40503c3be3d.
GH-18 More bugfixes & code cleanup

Bug: unhighlight background when all connections are deleted; netlabel
name change on object name change
GH-18 Bugfix: added check for non-connection obj before deletion