[gnome-builder] build: add AUTHORS file with list of current contributors.

[Christian Hergert <chergert src gnome org>]

commit 60d05588da9de0f5a7a131d78ec74c7027a5c3b5
Author: Christian Hergert <christian hergert me>
Date:   Thu Sep 11 13:03:28 2014 -0700

    build: add AUTHORS file with list of current contributors.

 AUTHORS |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/AUTHORS b/AUTHORS
new file mode 100644
index 0000000..8d4beeb
--- /dev/null
+++ b/AUTHORS
@@ -0,0 +1,3 @@
+Carlos Soriano
+Christian Hergert
+Jakub Steiner