added Bialystok map; renamed bifurcation
reduce A.I. MSAM build production

they don't seem to know what it's for, and build a bit too many, (to the exclusion of other units sometimes, for some reason).
added stealth raider icon
added icon for stealth raider trike to bits
added d2k map, sand_everywhere
updated sand_everywhere map
made construction yard "base provider" (build radius)
fix Fremen to have rocket launcher, like in the original.
made buildings require base provider (be in build radius)

Rationale:
Engineers right now can capture a building and then start building turrets in your base. Some might view this as legitimate but it is a pretty ridiculous strategy and makes game kind of unfun.
Part of why it's a problem is that turrets are quite powerful in this mod, and hard to kill.
The build radius is set to 30, which is very high, so it shouldn't be noticeable for most players in most games. But it will stop you from being able to build across the map.
harvester speed 7 -> 6

Harv was a bit too fast. Tanks have been slowed, so it should be too.
switched back to RA explosions.
Until translucent effects are introduced, we should use the RA explosions,
which look better than what we currently have.
devastator gfx; & sonic weapons str. Fire fixed.
added bigboom; made explosions better fits
re-arranged explosions in sequences.yaml for ease
general fix-ups.
re-added old nuke missile, with RA palette (fix)
renamed sand_everywhere; added larger version
Merge pull request #3217 from pchote/psydev-fixup

D2K / C&C updates