[gnome-apps-nightly] epiphany.flatpakref: Add warning comment

[Michael Catanzaro <mcatanzaro src gnome org>]

commit b0d7b3c321d24a25887cc22f6c9d53453c41e75c
Author: Michael Catanzaro <mcatanzaro posteo net>
Date:   Wed Mar 20 14:18:42 2019 +0000

    epiphany.flatpakref: Add warning comment

 epiphany.flatpakref | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/epiphany.flatpakref b/epiphany.flatpakref
index faa0860..888dd56 100644
--- a/epiphany.flatpakref
+++ b/epiphany.flatpakref
@@ -1,3 +1,5 @@
+# Please keep this in sync with webkitgtk.org:
+# https://github.com/WebKitGTK/webkitgtk.org/blob/master/epiphany-tech-preview.flatpakref
 [Flatpak Ref]
 Title=GNOME Web
 Name=org.gnome.Epiphany.Devel