Times adjustments on Scene
Move timing to constants & instance properties
Merge pull request #4 from rafaelks/times-adjustments

Improvement: use timing from constants & instance properties
Create a new class to Background SpriteNode
Start using new class on PlayingScene
Merge pull request #5 from rafaelks/separate-nodes-classes

Improvement: separate BackgroundSpriteNode in a separated class
Create a AirPlaneObstacle class & images
Add Obstacles to BackgroundNodes
Adjustments on Obstacles
AirPlane fire bullet feature added.
Resolve conflicts
Merge pull request #6 from rafaelks/fire-bullet

New Feature: Fire bullet Action
Code adjustments
Merge branch 'master' into core-motion

Conflicts:
	AirWar.xcodeproj/project.pbxproj
	AirWar/Controllers/Scenes/AWPlayingScene.m