Add some cross-references to NSEdoc for recent scripts

scripts/http-cookie-flags.nse

@@ -55,6 +55,7 @@ by it will be checked in addition to the root.
 -- </table>
 --
 -- @see http-enum.nse
+-- @see http-security-headers.nse
 
 categories = { "default", "safe", "vuln" }
 author = "Steve Benson"

scripts/http-headers.nse

@@ -24,6 +24,8 @@ Performs a HEAD request for the root folder ("/") of a web server and displays t
 --
 --@args path The path to request, such as <code>/index.php</code>. Default <code>/</code>.
 --@args useget Set to force GET requests instead of HEAD.
+--
+--@see http-security-headers.nse
 
 author = "Ron Bowes"
 

scripts/smb-double-pulsar-backdoor.nse

@@ -14,6 +14,8 @@ https://github.com/countercept/doublepulsar-detection-script
 ---
 -- @usage nmap -p 445 <target> --script=smb-double-pulsar-backdoor
 --
+-- @see smb-vuln-ms17-010.nse
+--
 -- @output
 -- | smb-double-pulsar-backdoor:
 -- |   VULNERABLE:

scripts/smb-vuln-ms17-010.nse

@@ -5,7 +5,7 @@ local string = require "string"
 
 description = [[
 Attempts to detect if a Microsoft SMBv1 server is vulnerable to a remote code
- execution vulnerability (ms17-010). 
+ execution vulnerability (ms17-010, a.k.a. EternalBlue).
 
 The script connects to the $IPC tree, executes a transaction on FID 0 and
  checks if the error "STATUS_INSUFF_SERVER_RESOURCES" is returned to
@@ -26,6 +26,8 @@ References:
 -- @usage nmap -p445 --script smb-vuln-ms17-010 <target>
 -- @usage nmap -p445 --script vuln <target>
 --
+-- @see smb-double-pulsar-backdoor.nse
+--
 -- @output
 -- Host script results:
 -- | smb-vuln-ms17-010:
@@ -157,7 +159,7 @@ action = function(host,port)
     description = [[
 A critical remote code execution vulnerability exists in Microsoft SMBv1
  servers (ms17-010).
-]],
+    ]],
     references = {
       'https://technet.microsoft.com/en-us/library/security/ms17-010.aspx',
       'https://blogs.technet.microsoft.com/msrc/2017/05/12/customer-guidance-for-wannacrypt-attacks/'