Make level editor

[GoogleFrog]

A level editor will get people making more levels. It could perhaps be part of the main program accessible via the menu. This is at least a good final structure.

The first level editor does not need to do everything. It could support:

• Adding walls and changing level size.
• Adding platforms and setting On/Off positions.
• Adding portals and setting common variables (Win, Relative, Time)
• Adding pickups.
• Adding switches.
• Initial guy and boxes.
  The level editor would add appropriate triggers for platforms, switches and pickups. Initially the editor would allow for easy placement of level elements. It does not need to do everything (linking platform switches) and it does not need to enable all features (eg the box-o-matic or complex switch logic).

(Perhaps better as a milestone?)