Added discord alert

lgsm/config-default/config-lgsm/rustserver/_default.cfg

@@ -41,6 +41,11 @@ fi
 
 ## Notification Alerts
 # (on|off)
+
+# Discord Alerts | https://github.com/GameServerManagers/LinuxGSM/wiki/Discord
+discordalert="off"
+discordwebhook="https://discordapp.com/api/webhooks/12345/abcd12345"
+
 # Email Alerts | https://github.com/GameServerManagers/LinuxGSM/wiki/Email
 emailalert="off"
 email="email@example.com"