Populating admin email with user signup email

closes #775

core/server/controllers/admin.js

@@ -171,12 +171,13 @@ adminControllers = {
             email: email,
             password: password
         }).then(function (user) {
-
+            api.settings.edit('email', email).then(function () {
                 if (req.session.user === undefined) {
                     req.session.user = user.id;
                 }
                 res.json(200, {redirect: '/ghost/'});
-        }, function (error) {
+            });
+        }).otherwise(function (error) {
             res.json(401, {error: error.message});
         });