CC-2579: Upgrad fails 1.8->1.9

- moved all the config files to each upgrade dir
- also fixed back up name of 1.9.0 conifg to 1.9.0(from 1.8.1)

install_minimal/upgrades/airtime-1.8.1/airtime-upgrade.php

@@ -112,7 +112,6 @@ function LoadConfig($CC_CONFIG) {
  */
 function CreateIniFiles()
 {
-    global $AIRTIME_SRC;
     global $AIRTIME_PYTHON_APPS;
 
     if (!file_exists("/etc/airtime/")){
@@ -122,7 +121,7 @@ function CreateIniFiles()
         }
     }
 
-    if (!copy($AIRTIME_SRC."/build/airtime.conf.181", CONF_FILE_AIRTIME)){
+    if (!copy("airtime.conf.181", CONF_FILE_AIRTIME)){
         echo "Could not copy airtime.conf to /etc/airtime/. Exiting.";
         exit(1);
     }