Create CSF_.pl

New plugin that displays ConfigServer Firewall (CSF) data.
![csf_deny_cluster-day](https://f.cloud.github.com/assets/5884608/1497831/9f65d0bc-4818-11e3-866e-1cdce0fa7d37.png)
![csf_deny_country-day](https://f.cloud.github.com/assets/5884608/1497832/9f6ae28c-4818-11e3-85b3-7043d674e6f0.png)
![csf_deny_service-day](https://f.cloud.github.com/assets/5884608/1497833/9f6fed04-4818-11e3-87fc-06167c83c00d.png)