[airstrike] major changes

[Ulf Ekström]

> What happened to these changes? You did not commit anything after that
> mail.
>
> Erik
>


Hmm, yes, I know. I started to remove all the object locking, but then
lost my energy at about 80% done, so I didn't commit anything. I will
have a look at it tonight and see if I can finish the changes. My plan
was to simplify the who reference system a bit, and eventually make it
possible to save the whole state of the game inbetween frames, by
placing some restrictions on the memory management and the message
system.

Ulf