fixed bug that allowed creation of two edges between a pair of nodes after importing a topology, added output of a message when redirecting a edge to form a situation of "two edges - one pair of nodes" or "edge starts and ends in same node"
fixed bug that allowed creation of two edges between a pair of nodes after importing a topology, added output of a message when redirecting a edge to form a situation of "two edges - one pair of nodes" or "edge starts and ends in same node"

theuerse/netedit,theuerse/netedit