Replace the throwing of a NonImplementedException in MyNpcCharacter, so that

the SimpleModule doesn't prevent the start of the region server, if used.
Note: This module doesn't do anything sensible; it only serves as an example.

OpenSim/Region/Examples/SimpleModule/MyNpcCharacter.cs

@@ -1000,7 +1000,7 @@ namespace OpenSim.Region.Examples.SimpleModule
 
         public bool AddGenericPacketHandler(string MethodName, GenericMessage handler)
         {
-            throw new NotImplementedException();
+            return true;
         }
 
         #endregion