Created ContentPack class
Moved ResourceManager to ContentLoader
Created ContentManifest class
Switched ContentLoaders to use ContentManifest
Finished ContentPack class
Began modularizing ContentLoader
Created content package and Mergeable interface
Added plans for ContentLoader
Added methods to load index definitions
Added methods to load sounds, music, and images
Added method to load portals
Added method to load actions
Added method to load tiles
Added method to load entities
Added method to load lands
Added method to load worlds
Removed unneeded methods from loaders
Created Content class
Finished Content class
Added some methods to ContentPack for loading