Replace the obsolete race check from GiveUnitCrateAction.
Fixed drop-zone units
Merge pull request #5974 from pchote/cratefix

Fix unit collection crates and drop-zone maps.
Adds the RequiresPrerequisites field into ProvidesCustomPrerequisite and all the logic behind it.
Fix aircraft losing selection outside the map borders

Fixes #5651
Merge pull request #5965 from WolfGaming/CustomPrereqChange

Adds the RequiresPrerequisites field into ProvidesCustomPrerequisite
Merge pull request #5967 from obrakmann/fix5651

Fix aircraft losing selection outside the map borders
Fixes gem mine desert palette.
Merge pull request #5987 from reaperrr/gem-mine-palette

Fixes gem mine desert palette
Fix frozen actors being targetable under shroud. Fixes #5979, #5978.
Merge pull request #5989 from pchote/frozen-target-fix

Fix frozen actors being targetable under shroud.
Fix scripted paradrops.
Fix old-lua paradrop too.
Merge pull request #5988 from pchote/shellmap-paradrop

Fix scripted paradrops.
Play the correct race notification when repairing an ally’s structure.
Don’t cancel MoveAdjacentTo / MoveWithinRange when target becomes invalid.

Move to the last known position instead.  Fixes #5968.
Calculate a new path (and possibly new target cell) if the original path is blocked.
Fix a typo.
Merge pull request #5990 from pchote/repair-fix

Play the correct race notification when repairing an ally’s structure.
Merge pull request #5977 from pchote/oi-keep-moving

Don’t cancel MoveAdjacentTo / MoveWithinRange when target becomes invalid