CC-3841: Remove "airtime-show-recorder" initd script on upgrade

-fixed

install_minimal/upgrades/airtime-2.1.0/MiscUpgrade.php

@@ -5,6 +5,7 @@
 class AirtimeMiscUpgrade{
     public static function start($p_ini){
         self::adjustAirtimeStorPermissions($p_ini);
+        self::cleanupOldFiles();
     }
         
     public static function adjustAirtimeStorPermissions($p_ini){
@@ -15,4 +16,9 @@ class AirtimeMiscUpgrade{
         echo " * Updating /srv/airtime permissions to 02755".PHP_EOL;
         exec("chmod -R 2775 /srv/airtime");
     }
+    
+    public static function cleanupOldFiles(){
+        exec("rm -f /usr/bin/airtime-user");
+        exec("rm -f /etc/init.d/airtime-show-recorder");
+    }
 }