Fixup for release

Fixes the grammar on the SMTP enumeration module and the Cisco CDP
module, and adds a more informative description and reference for the
CDP module introduced on PR rapid7#4061.

Author: Tod Beardsley

modules/auxiliary/scanner/smtp/smtp_ntlm_domain.rb

@@ -14,7 +14,7 @@ class Metasploit3 < Msf::Auxiliary
   def initialize
     super(
       'Name'        => 'SMTP NTLM Domain Extraction',
-      'Description' => 'Extract the Windows domain name from a SMTP NTLM challenge.',
+      'Description' => 'Extract the Windows domain name from an SMTP NTLM challenge.',
       'References'  => [ ['URL', 'http://msdn.microsoft.com/en-us/library/cc246870.aspx' ] ],
       'Author'      => [ 'Rich Whitcroft <rwhitcroft[at]digitalboundary.net>' ],
       'License'     => MSF_LICENSE

modules/auxiliary/spoof/cisco/cdp.rb

@@ -9,11 +9,20 @@ class Metasploit3 < Msf::Auxiliary
   include Msf::Exploit::Capture
 
   def initialize
+
     super(
       'Name'        => 'Send Cisco Discovery Protocol (CDP) Packets',
-      'Description' => 'This module sends Cisco Discovery Protocol (CDP) packets',
+      'Description' => %q{
+        This module sends Cisco Discovery Protocol (CDP) packets. Note that any responses
+        to the CDP packets broadcast from this module will need to be analyzed with an
+        external packet analysis tool, such as tcpdump or Wireshark in order to learn more
+        about the Cisco switch and router environment.
+      },
       'Author'      => 'Fatih Ozavci <viproy.com/fozavci>',
       'License'     =>  MSF_LICENSE,
+      'References'  => [
+        [ 'URL', 'http://en.wikipedia.org/wiki/CDP_Spoofing' ]
+      ],
       'Actions'     => [
         ['Spoof', { 'Description' => 'Sends CDP packets' }]
       ],