fabrikbauer - speedup

[Dwachs]

Here is a patch that should accelerate industry placement. In current code, first suitable places are searched, and then one is chosen randomly. Patch reverses the order: first the search starts at a random location, and then the first suitable location is returned. Please test

[prissi]

When running out of places I did not see much change. Otherwise it is indeed much faster.

SOmehow I think the clustering (radius) stll needs to be more map dependent.

EDIT: Please submit.

[TurfIt]

   Looks good.