Implement phpseclib

Implemented phpseclib library to login as root and perform root actions
The following features requires to login with a user having root
permission:
shutdown/reboot your raspberry
start/stop services
mount/unmount partitions

Don't need to add www-data to the sudoers file

![login](https://f.cloud.github.com/assets/1665768/1034662/21258726-0f1d-11e3-8db3-f0caa9e2e412.png)
![loginfailed](https://f.cloud.github.com/assets/1665768/1034658/20ee9efa-0f1d-11e3-977d-ecf2520b4ec3.PNG)
![login_ok](https://f.cloud.github.com/assets/1665768/1034659/20f660ae-0f1d-11e3-8fed-5ba4301ba014.PNG)
![login_disks](https://f.cloud.github.com/assets/1665768/1034660/20fbfcb2-0f1d-11e3-8e0c-e80f5297faf0.PNG)
![login_disks_unmount](https://f.cloud.github.com/assets/1665768/1034661/211f2cc8-0f1d-11e3-81cf-8c48c6569f46.PNG)
![login_disks_ok](https://f.cloud.github.com/assets/1665768/1034663/2137986c-0f1d-11e3-9cd2-8dadfb1377f8.PNG)