Level Editor Improvements

[mattbruv]

We eventually want a page where we can create custom levels, see how they will be rendered, and then give the player the option to save them (to perhaps local storage for now) and then to host a game with them.

Level Editor Improvements:

• Limit amount that a user can zoom in/out when scrolling on the game world to a reasonable limit
• Save worlds to local storage? (another option instead of downloading maps in order to save them)
• Allow loading custom maps when hosting a game (should be easy to support this in the engine code)
• Add a button or way to reset the zoom scale to 1?
• Add a way to load an existing level from file, or to load in one of the original game maps as a base
• Make scrolling to zoom in the game world not scroll the page too
• Display character to piece mapping information in a more aesthetic way, perhaps even including images of the game world item