Modified various files to enable designers to make builds.

*Namely, created conditional statements to test to see if the level uses
upgrades (previously MainMenu script assumed it did, and threw an error
if you attempted to load a level that was missing the upgradeManager
script).
*Modified the default project and editor settings to a larger default
resolution for builds, to make it easier to see on a PC.
* Modified LevelSelectScreen to test how to setup levels