Multi World NPCs + patch on Player interactions

Made NPCs now work properly on multiworld system. Solved multiple issues
regarding Player Shops not giving back items properly when owner exits.
Added restriction on changing channels at FM rooms, preventing shop
owner entering Cash Shop.

scripts/npc/2120003.js

@@ -0,0 +1,10 @@
+/* @Author SharpAceX
+        Name: Maid
+        Map(s): Foyer.
+        Info: Maid
+*/
+
+function start() {
+	cm.sendOk("Hello and welcome, dear guest. The Master has prepared some wonderful games for you to enjoy tonight.");
+	cm.dispose();
+}