Merge pull request #80 from jocelynlih/paul

removed an incorrect comment
Merge pull request #81 from jocelynlih/paul

Paul
Merge pull request #82 from jocelynlih/paul

a tad of code cleanup and fixed the disappearing level.
Merge pull request #83 from jocelynlih/paul

This update changes how we build levels.
Merge pull request #84 from jocelynlih/paul

More fixes
removed unneccessary part of int literal
fixes bug with trying to load multiple scenes at once
Hide Status Bar in View Controller.
Update Readme file
Update ReadMe.md
Adding life line node playground for chapter
Merge pull request #85 from jocelynlih/ankur-add-more-playgrounds

Adding life line node playground for chapter
Removing unnecessary styles
Updating method signatures
game over scenes
It turns out there is a bug in iOS that doesn't cleanup scenes properly. I find this hard to believe, but the solution to our crashes proves that this is an issue (or there is a scarier systemic problem at work here.)

Incidentally, during testing, I noticed another bug - as you played the game over and over without restarting, after about 15 times through the level, it would get slower and slower and use more and more memory. The frame rate would get down to about 7FPS (and even lower if I would keep testing) and the memory footprint would reach over a GB (!!). This fix solves this problem as well.

The fix is to cleanup the currently presented scene recursively before presenting the new scene.