Adding documentation

Adding module documentation for ws_dos.

Author: rknellx

documentation/modules/auxiliary/dos/http/ws_dos.md

@@ -0,0 +1,61 @@
+## Vulnerable Application
+ 
+   [ws < 1.1.5 || (2.0.0 , 3.3.1)]
+   (https://nodesecurity.io/advisories/550)
+
+## Vulnerable Analysis
+
+	This module exploits a Denial of Service vulnerability in npm module "ws".
+	By sending a specially crafted value of the Sec-WebSocket-Extensions header 
+	on the initial WebSocket upgrade request, the ws component will crash.
+
+## Verification Steps
+
+1. Start the vulnerable server using the sample server code below `node server.js`
+2. Start `msfconsole`
+3. `use auxiliary/dos/http/ws_dos`
+4. `set RHOST XXX.XXX.XXX.XXX`
+5. `run`
+6. The server should crash
+
+## Options
+
+	None.
+
+## Scenarios
+
+## Server output from crash
+```
+/Users/sonatype/Downloads/node_modules/ws/lib/Extensions.js:40
+    paramsList.push(parsedParams);
+               ^
+
+TypeError: paramsList.push is not a function
+    at value.split.forEach (/Users/sonatype/Downloads/node_modules/ws/lib/Extensions.js:40:16)
+    at Array.forEach (<anonymous>)
+    at Object.parse (/Users/sonatype/Downloads/node_modules/ws/lib/Extensions.js:15:20)
+    at WebSocketServer.completeUpgrade (/Users/sonatype/Downloads/node_modules/ws/lib/WebSocketServer.js:230:30)
+    at WebSocketServer.handleUpgrade (/Users/sonatype/Downloads/node_modules/ws/lib/WebSocketServer.js:197:10)
+    at Server.WebSocketServer._ultron.on (/Users/sonatype/Downloads/node_modules/ws/lib/WebSocketServer.js:87:14)
+    at emitThree (events.js:136:13)
+    at Server.emit (events.js:217:7)
+    at onParserExecuteCommon (_http_server.js:495:14)
+    at onParserExecute (_http_server.js:450:3)
+```
+
+## Sample server
+```
+const WebSocket = require('ws');
+const wss = new WebSocket.Server(
+{ port: 3000 }
+);
+wss.on('connection', function connection(ws) {
+console.log('connected');
+ws.on('message', function incoming(message)
+{ console.log('received: %s', message); }
+);
+ws.on('error', function (err)
+{ console.error(err); }
+);
+});
+```