CLOUDSTACK-2891. While adding a new vlan range if the new range extends an existing range then CS extends the existing range to include the new range.
This is done by checking if the last vlan in the new range is same as the start vlan of any existing range.
Since for a single vlan the start and the end vlan are the same the check goes to an infinite loop resulting in a java.lang.OutOfMemoryError: Java heap space error.
Remove the check for a single vlan because if an existing range starts with the single vlan then it implies that the range already exists