Tiles instead of Chars

[ras0219]

The Renderable component along with the MapView and anywhere else appropriate should be switched to use a more general "Glyph" or "Tile" type so that we can support non-textual rendering more easily.

When in a text-based render mode, these would collapse to some set of extended ascii (maybe unicode?) characters.

When in a graphical-tile-based render mode, these could be associated with some actual graphic assets (with the text-mode as a fallback).

[shadowpho]

Assigned this shadowpho guy. Hopefully he can make something happen.