schwerdt/AdventureGame — pull request #1 by schwerdt (2014-11-26 02:43:39+00:00)
Title: Added acceleration/deceleration to the image movement.

If no keys are pressed, the velocity is decreased slowly.
The factor used is 0.99*current_velocity to decrementing.
If arrow keys are pressed, the velocity is increased
in increments of 0.01. The acceleration is in image_class
(in the position update method).