Fixed AI Showdown in the Pacific from Eric

[WolfSpider]

I am testing some MP scenarios with a friend, and we did see that 2vAll AI Showdown in the Pacific had some issues with the objectives, I did edit the scenario and fixed following objectives:

- activate main objective to be active from scenario start.
- active the secondary objective to conquer the 4 harbors from scenario start.
- added the activation of the secondary objective to loose the harbor after the harbor was conquered.
- Changed the main objective check that it is won, as soon all naval forces are destroyed and not all forces.

- Updated version and description.

any question or comment, please ping me.

[Erik2]

Thanks