[ADD] zm_multi_pyramid_x

[Christmas]

Map: zm_multi_pyramid_x
Location: http://rapidshare.com/files/41316062..._pyramid_x.bsp
Reason: Too many ZM maps have wide open spaces with no real spot to defend yourself from zombies, barricades that are either too easy or too hard to defend against, and overall just poor planning.

This map features four zones: barricade (five small shacks for barricading), jump (multiple platforms in which to jump across and defend from zombies following you or attempting to get at you), hold out (multiple crawl spaces and rooms that do not need to be barricaded to defend against), and bunker (two small bunkers to barricade and defend against attacking zombies). Each has its own unique flavor and the map itself provides a fresh style to the standard ZM map.