Issue:AiSee crash due to several near edges

Description:	there are several constellations of nearedges and bentnearedges which lead to a program crash
Extension / Version:	aiSee   /   2.2
Type / Status:	Bug   /   open

Problem

The following graph definition causes a memory violation:

graph: {
  title: "A"
  rightnearedge: { source:"A" target:"B" }
  leftnearedge: { source:"A" target:"C" }
  rightbentnearedge: { source:"A" target:"D" }
}

There are more constellations which have the same effect. The following piece of php code tries to identify all dangerous constellations:

foreach ($edges as $edgeId => $edge) {
	$n=$ln=$rn=$b=$lb=$rb=0;
	$edgeKind = $edge['kind'];
	if	($edgeKind == 'near') 		$n++;
	else if ($edgeKind == 'leftnear') 	$ln++;
	else if ($edgeKind == 'rightnear') 	$rn++;
	else if ($edgeKind == 'bentnear')	$b++;
	else if ($edgeKind == 'leftbentnear') 	$lb++;
	else if ($edgeKind == 'rightbentnear') 	$rb++;
		
	foreach ($edges as $nEdgeId => $nEdge) {
		$from = $edge['source'];
		if ($nEdgeId <= $edgeId || $nEdge['source'] != $from) continue;
		if ($nEdge['target'] == $edge['target']) {
			$this->error("near edges at '$from' point to the same other node '".$edge['target'],'');
		}
		$nEdgeKind = $nEdge['kind'];
		if 	($nEdgeKind == 'near') 		$n++;
		else if ($nEdgeKind == 'leftnear')	$ln++;
		else if ($nEdgeKind == 'rightnear') 	$rn++;
		else if ($nEdgeKind == 'bentnear')	$b++;
		else if ($nEdgeKind == 'leftbentnear') 	$lb++;
		else if ($nEdgeKind == 'rightbentnear')	$rb++;
		//$this->parser->errorText .= "checking $edgeKind edge $edgeId against $nEdgeKind edge $nEdgeId at $from: $n,$ln,$rn  $b,$lb,$rb:\n";			
				
		if (($rn+$ln>=2 && $rb+$lb>=1) ) $this->error("too many near (bent) edges at '$from'",'');
	}
}