Add DLSw leak capture module for CVE-2014-7992

Note: I have a zip file that contains a full setup to test for this vulnerability.  It has 2 Win VMs and a GNS3 configuration with 3 routers to enable testing. I would be happy to share. Otherwise you need to build a working DLSw setup to test.
This will false-positive when you connect to something that just spews data.  Is there any way we can validate that this is a DLSw response?