Add reserve property to particle emitter config

Author: vladforsh

src/gameobjects/particles/ParticleEmitter.js

@@ -863,6 +863,11 @@ var ParticleEmitter = new Class({
             this.setFrame(config.frame);
         }
 
+        if (HasValue(config, "reserve"))
+        {
+            this.reserve(config.reserve);
+        }
+
         return this;
     },