[gnome-calculator] Fixed markup error in about (bgo#772990)

[Robert Roth <robertroth src gnome org>]

commit 6f9b2dccb5550c9a6bf23267057827475ad96430
Author: Robert Roth <robert roth off gmail com>
Date:   Sat Oct 15 21:01:15 2016 +0300

    Fixed markup error in about (bgo#772990)

 src/gnome-calculator.vala |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/gnome-calculator.vala b/src/gnome-calculator.vala
index eb1c0cb..80ded6e 100644
--- a/src/gnome-calculator.vala
+++ b/src/gnome-calculator.vala
@@ -266,7 +266,7 @@ public class Calculator : Gtk.Application
             "Robert Ancell <robert ancell gmail com>",
             "Klaus Niederkrüger <kniederk umpa ens-lyon fr>",
             "Robin Sonefors <ozamosi flukkost nu>",
-            "Robert Roth <robert roth off gmail com",
+            "Robert Roth <robert roth off gmail com>",
             null
         };
         string[] documenters =