Jebel Barkal random map, fixes #5040.

Features:
* a mountain created in atlas, refs #4816
* a procedurally generated city, refs #5061
* scripted city guards and reoccuring gaia attackers
* attacker composition depend on the remaining buildings of the city
* random irrigation canals that indirectly increase the distance between
the two teams

Needs map description and player feedback to become complete.
Hill based on the Napata Reconstruction hill created by Skhorn of
8615acb2fc.
Consulting By: Sundiata, Skhorn
This was SVN commit r21488.

binaries/data/mods/public/maps/random/jebel_barkal.json

@@ -0,0 +1,14 @@
+{
+	"settings" : {
+		"Name" : "Jebel Barkal",
+		"Script" : "jebel_barkal.js",
+		"Description" : "The unknown.",
+		"Preview" : "jebel_barkal.png",
+		"Keywords": ["new", "trigger"],
+		"CircularMap": true,
+		"TriggerScripts" : [
+			"scripts/TriggerHelper.js",
+			"random/jebel_barkal_triggers.js"
+		]
+	}
+}