[airstrike] Recent changes.

[Ulf Ekström]

> After compiling I get "Can't chdir() to ../share, quitting",
> so I created a bin/ directory and moved the "airstrike" binary there,

Ah, this is a bit stupid. The current binary expects to be run from
src/ (this is
obviously only a temporary solution). In linux it should work if you run it from
src/, in windows this has to be fixed in the code. 

At the start the program tries to chdir() to the share directory. As
far as I know there is no chdir()
function under windows (It's called something else, or?). Therefore we
implement our
own chdir() in src/core/compat.c.  However this is only done for Unix
systems. If anyone would
like to do it for windows I would be happy.

> however, this results in: "airstrike: engine/engine.c: engine_setup:
> Assertion `"f != 0 && defaults not found"' failed."
> 
> What did I do wrong?

It's the fault of the stupid code I would say. Also the Makefile in
the main archive creates the
executable in a place from where is cannot be run(!), not so good. I
will fix it.

Ulf