Fixes#179
The Valkyrie goal level has two drawbridges and one of them was set to
have 50:50 chance to be closed (raised). But 'random' for drawbridge
open/closed (or lowered/raised) state was always choosing open (lowered).
This fixes that and also changes that level to have the old settings
(southern open, northern 50:50) for 75% of the time and new settings
(both 50:50) for 25% of the time. So there's now a 12.5% chance that
both will be closed instead of both always being open (due to the bug
with handling random).
81d755a9e0