Refactor tile/obs save/load system

* Now uses Tile Class names and naming conventions
* Editor autodetects tile types and cycles through them
* Set tile and obs save data by type
* Game auto-instantiates Tile classes by name and tileset number.
* Should mean that adding tiles is as easy as creating the art (with
proper names), writing the class, and adding the tile name to the
editor's tile list variable.
* Can add a new tileset for an existing tile by creating the next image
set with appropriate tileset number suffix and adding the frameset to
the animation object; auto added to editor as long as the art exists