Added basic circle obstacle; building out obstacle system
Color changes; updates to variables
Merge commit 'fb004259760924823c16313961ee79fb1af1c622' into dev

Conflicts:
	src/Player.cpp
Art and stuff
Mid-art update
Visual updates
Merge branch 'dev' into aaron_mac

Conflicts:
	Field1.xcodeproj/project.pbxproj
	bin/data/ART/background.png
	src/GameScreen.cpp
	src/GameScreen.h
	src/GameVariables.h
	src/Player.cpp
	src/Player.h
	src/Screen.cpp
Playing with listeners (needs a fix)
Made (temporary) globalcollisionlistener & fixed player constructor
Finished collision handling
Swapping base classes to generic GameObject ; collision detection not working again
level handling
Fixed object velocity
Merge remote-tracking branch 'origin/shervin' into aaron_mac

Conflicts:
	Field1.xcodeproj/project.pbxproj
	bin/data/variables.xml
	libraries/of_v0.7.4_osx_release/addons/ofxBox2d/src/ofxBox2dBaseShape.h
	libraries/of_v0.7.4_osx_release/addons/ofxBox2d/src/ofxBox2dCircle.h
	libraries/of_v0.7.4_osx_release/addons/ofxBox2d/src/ofxBox2dRect.h
	src/Constants.h
	src/GameScreen.cpp
	src/GameScreen.h
	src/GameVariables.h
	src/Goal.cpp
	src/Goal.h
	src/Model.cpp
	src/Model.h
	src/Player.cpp
	src/Player.h
	src/SquareObstacle.cpp
	src/SquareObstacle.h
	src/collisionscorekeeper.cpp
	src/collisionscorekeeper.h
Merge fixes
Added XML Saving