(weekly) update - editor works

Hello!

I implemented a simple editor so I can create a few non-random levels now.
I had to enhance the data structure storing the village because the
undo operation of the editor needed some informations about the
basic topology of my village.
Because of this enhancement I can now create levels that contain 'dead' regions
(currently it is a complete 25x25 grid of houses without gaps).
This will be very nice, but I have to touch that editor again.

Stay tuned ...