Extract a UiManager class from MainFrame to switch between the screens
Update docs
Merge branch 'ui-switch'
Add a pulse generator for continous changes
Implement an immutable 2D-vector for movement
Fix drawing sizes
Reduce player size to ease movement
Throw on normalizing the null vector
Implement movement direction with a vector
Add some documentation for pulses and how they are handled in LogicHandler
Extract the game logic into a class
Refactor game logic
Fix a bug
Fix coding style
Simplify code
Merge branch 'pulse'
Put a level abstraction layer above rooms
Add Player#maxHitPoints
Add Player#lives
Add some docstrings