Remove 2 job & refactor tower spec

src/prototype.tower.js

@@ -1,15 +1,15 @@
 StructureTower.prototype.defend =
     function () {
-        // find closes hostile creep
+
+        // Defend Base
         var target = this.pos.findClosestByRange(FIND_HOSTILE_CREEPS);
-        // if one is found...
         if (target != undefined) {
-            // ...FIRE!
             this.attack(target);
         }
-        
+
+        // Repair structure & only first 100k of wall
         var closestDamagedStructure = this.pos.findClosestByRange(FIND_STRUCTURES, {
-            filter: (structure) => structure.hits < structure.hitsMax
+            filter: (structure) => structure.hits < structure.hitsMax && (structure.structureType != STRUCTURE_WALL || structure.hits < 100000)
         });
         
         if(closestDamagedStructure) {