user_name -> username

Change-Id: I2cb601f7e0eeb36a27e9dad662f3554a0092ab18
diff --git a/utils.php b/utils.php
index 44160c0..41996fb 100644
--- a/utils.php
+++ b/utils.php
@@ -67,11 +67,11 @@
     $string = str_replace("{{last_name}}", $user->last_name, $string);
     $string = str_replace("{{email}}", $user->email, $string);
     $string = str_replace("{{organization}}", $user->organization, $string);
-    $string = str_replace("{{username}}", $user->user_name, $string);
+    $string = str_replace("{{username}}", $user->username, $string);
     return $string;
 }
 
 function user_to_string(User $user)
 {
-    return $user->first_name . " " . $user->last_name . " <" . $user->email . "> " . $user->organization . " " . $user->user_name;
+    return $user->first_name . " " . $user->last_name . " <" . $user->email . "> " . $user->organization . " " . $user->username;
 }
\ No newline at end of file