Fix missing AMQPConnection errors in setup

Also fixes them elsewhere, apart from having switched to a vendorized version, I also used one that is already namespaced.

The easy way out here is to use it in the namespaced fashion, it is only used in a few places and I know the library well enough to be certain that nothing much changed apart from the namespacing.

airtime_mvc/build/airtime-setup/load.php

@@ -109,7 +109,7 @@ function checkRMQConnection() {
         $ini = parse_ini_file(BUILD_PATH . "airtime.example.conf", true);
     }
 
-    $conn = new AMQPConnection($ini[RMQ_INI_SECTION]["host"],
+    $conn = new \PhpAmqpLib\Connection\AMQPConnection($ini[RMQ_INI_SECTION]["host"],
                                $ini[RMQ_INI_SECTION]["port"],
                                $ini[RMQ_INI_SECTION]["user"],
                                $ini[RMQ_INI_SECTION]["password"],