CC-2725: /etc/airtime/liquidsoap.cfg should not be world-readable

-done

install_minimal/upgrades/airtime-1.9.4/airtime-upgrade.php

@@ -0,0 +1,15 @@
+<?php
+
+class Airtime194Upgrade{
+
+    const CONF_FILE_LIQUIDSOAP = "/etc/airtime/liquidsoap.cfg";
+    const CONF_PYPO_GRP = "pypo";
+    
+    public static function upgradeLiquidsoapCfgPerms(){
+        chmod(self::CONF_FILE_LIQUIDSOAP, 0640);
+        chgrp(self::CONF_FILE_LIQUIDSOAP, self::CONF_PYPO_GRP);
+    }
+
+}
+
+Airtime194Upgrade::upgradeLiquidsoapCfgPerms();