Map link: http://resource.openra.net/maps/20494/
Changes:
* Renamed from `Behind The Veil` to `Behind the Veil`
* Replaced chain link with walls in the middle to protect oil derricks
from direct attacks
* Added barrels to the middle area. A middle oil derrick can be
captured only from 2 spots (if barrels are not destroyed)
* Added barrels between side ridges
* Fixed some bad road tiles (thanks to Frame Limiter)
* Widen side passages to corner expansions by 1 cell
