I added MainMode and EggScramble mode.  I was starting to implement a strategy pattern for the GameLayer::Update method.
GameLayer is an abstract class, EggScrambleModeLayer and MainModeLayer are concrete.  The three are implementing the template method pattern.
EggScramble layer takes a levelNumber argument.  Scoring has been separated for egg scramble and main modes.
Vehicles gradually move faster in egg scramble mode.
Added disappearing logs.  The logic stil needs to be cleaned up.
Chicken dies when the log beneath it disappears.  Fixed the bug at the beginning of the second level due to phantom vehicles killing the chicken.  Added the project folders for other OSes.
Added a VehicleFactory.  Starting to refactory dimension referencing.
The _currentPosition property has been removed from the Chicken class.  The chicken is no longer visible on the GameOver screen.
Removed some unnecessary code and updated the TODO.
Added a getRandomValidLaneNumber function to the Level class.
I moved some dimension-related functions from GameLayer to Dimensions.
Chicken can only move within the playable area.
Chicken spawns on sidewalk.  Using _dimensions in Lane class.  Fixed bug where program crashes when a chicken riding on a log hits the edge of a screen.
Pulled out some common functions into a namespace called GameFunctions.
I added comments to GameFunctions and fixed a bug in Level so that a egg can be moved to any lane.  Level plists have been updated.