Collection of scripts to assist Ubuntu on the Dell XPS 12

• flipscreen.sh: Swap the state of your screen between "normal" and "inverted" (for tablet mode). Most useful when bound to the 'Auto-rotate' button (received as Super+O by Ubuntu).
• login.sh: I needed the scrolling/acceleration values for the touchpad to something much different to what the GUI permits, so these are the commands for those.