Added Wordpress XMLRPC DoS

This abuses the currently XMLRPC DoS vulnerability in Wordpress.

### Verification steps
- [x] Install Wordpress (I used 3.9.1) and disable automatic updates so it will not update to 3.9.2 during your tests https://www.firefart.at/how-to-install-wordpress/
- [x] Run the exploit against the installation
- [x] Watch CPU consumption and MySQL connections running out

![apache](https://cloud.githubusercontent.com/assets/105281/3844962/ce58c2b0-1e4d-11e4-92ec-01cbf7b6c845.png)