LUBUNTU - enable hibernation - Ubuntu 15.04 (vivid)

1. CTRL+SHIFT+T => opens terminal
2. sudo nano /etc/polkit-1/localauthority/50-local.d/com.ubuntu.enable-hibernate.pkla
3. Enter your root password.
4. Copy-paste the following lines:

     [Re-enable hibernate by default in upower]
     Identity=unix-user:*
     Action=org.freedesktop.upower.hibernate
     ResultActive=yes
     
     [Re-enable hibernate by default in logind]
     Identity=unix-user:*
     Action=org.freedesktop.login1.hibernate
     ResultActive=yes

5. Save and close.