Add explanation about AllowModFunctions to OpenSim.ini.example

This switch allows scripts to pass messages to modules via the modSendCommand() function
Modules can then send messages back to scripts via the link_message LSL event through
invoking DispatchReply() on OpenSim.Region.Framework.Interfaces.IScriptModuleComms

bin/OpenSim.ini.example

@@ -987,6 +987,11 @@
     ; Compile debug info (line numbers) into the script assemblies
     CompileWithDebugInformation = true
 
+    ; Allow the user of mod* functions.  This allows a script to pass messages
+    ; to a region module via the modSendCommand() function
+    ; Default is false
+    AllowMODFunctions = false
+
     ; Allow the use of os* functions (some are dangerous)
     AllowOSFunctions = false