Add old GMCP Enabled Script

@iLPdev y travaille déjà.

Depuis le 20/7/2020.

This is the XML for my old GMCP Enabled script. It's technically more accurate that what is in discMapper currently, because it only runs when the `sysProtocolEnabled` event fires and the protocol is, in fact, GMCP. I'm just too tired ATM to mess with it.

```

<name>dsGMCPEnabled</name>
<packageName></packageName>
<script>function dsGMCPEnabled(_, protocol)
if protocol == "GMCP" then
map.echo(" - GMCP Enabled")
end
end

sysProtocolEnabled

```