Change score display

 * Font size is now relative to screen size
 * Position changed to above the health bar
Add game over screen

 * Now shows game over screen after health goes zero
 * Added DisplayPanel to an xml layout which is used instead
   for setContentView
Change splash button background

 * Added image instead of xml drawable
 * Changed color from white to blue
 * Changed "ButtonSplash" style
Change game_over.png

 * Added white background to the game_over image
Merge branch 'master' into game_over
Change game_over screen layout and graphics

 * Buttons now appear side by side
 * game_over text image is improved
   (slight black edge no longer visible)
Add slide feature

 * Swiping down causes stickman to slide
Change splash button spacing