Clean up a bunch of stuff

- Channel typing data is now a Map
- Client properties on structures are now non-enumerable and
non-configurable

src/structures/PartialGuild.js

@@ -15,30 +15,35 @@ class PartialGuild {
      * @type {Client}
      */
     this.client = client;
+    Object.defineProperty(this, 'client', { enumerable: false, configurable: false });
+
     this.setup(data);
   }
 
   setup(data) {
-    /**
-     * The hash of the guild splash image, or null if no splash (VIP only)
-     * @type {?string}
-     */
-    this.splash = data.splash;
     /**
      * The ID of this guild
      * @type {string}
      */
     this.id = data.id;
-    /**
-     * The hash of this guild's icon, or null if there is none.
-     * @type {?string}
-     */
-    this.icon = data.icon;
+
     /**
      * The name of this guild
      * @type {string}
      */
     this.name = data.name;
+
+    /**
+     * The hash of this guild's icon, or null if there is none.
+     * @type {?string}
+     */
+    this.icon = data.icon;
+
+    /**
+     * The hash of the guild splash image, or null if no splash (VIP only)
+     * @type {?string}
+     */
+    this.splash = data.splash;
   }
 }