Added implementation for templates and stubbed out interface for tile
editing. Discovered that the entire level editor will have to be
refactored to allow for an easy to use Template editor that feels the
same graphically as the level editor. In the meantime, may also want to
add support for the command pattern for a possible eventual
implementation of undo/redo.
Refactored out Paintbrush as a common element from main editor and added
utility class. First attempt at implementing interface failed horribly,
so those changes were reversed. Will have to revise design
Stubbed out with a bit of implementation a new TileMap class. This is a
bit of a focus shift; before I can implement templates, I must refactor
the Tile[][] that was used into a separate class so that tilemaps can
easily be rendered outside of actual levels.