Tweaks to the TileSet
Tweaks to the TileSet

- Changed the default layout() method from raising an error to
  automatically showing all the available tiles in a grid
- Added a new function write() which allows you to use a TileSet as a
  Font to write a message. However it is very basic, and doesn't do
  anything fancy such as text wrapping.

alcarney/stylo,alcarney/stylo