Added code for Persistent Score & other fixes
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main.cpp
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- Modified code to work with new cumulativeScore

game.h
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- Modified render() & levelLoop to take in a Loadables struct instead
- Modified render() to print out the cumulativeScore

gameStage.h
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- Modified saveMenu() to take in a Loadables struct instead
- Modified pauseMenu() to take in a Loadables struct
- Fixed alignment problems with deleteMenu()

saves.h
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- Modified Loadables constructor to save the cumulativeScore

userInterface.h
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- Added printCumulativeScore()
- Cleaned up the look of other print HUD functions