Scientist doesn't need to draw himself.
Draw method can be told to draw a GameObject differently.

The Camera is going to draw all GameObjects from now on. If the Camera
zooms in then it needs to tell the GameObjects to draw themselves to
reflect that change.
Added partially implemented Camera.

Currently the ZoomToLocation does not snap to screen size. So scroll
wheel zooming will not work properly.
Camera now renders the GameObjects. Added some controls for zooming.

Messages are not drawn and have not been tested with the Camera. Use +/-
to zoom in/out, numpad 0 to reset zoom, and scroll wheel up to zoom in
(not fully implemented).