fix(app-config): Use parentheses to fix string concat in config

Changes:
- wrap `process.env.DOMAIN || ''` in parentheses to correct the order of the OR operator and string concat

Closes #466

app/templates/server/config/environment/index.js

@@ -44,24 +44,24 @@ var all = {
   facebook: {
     clientID:     process.env.FACEBOOK_ID || 'id',
     clientSecret: process.env.FACEBOOK_SECRET || 'secret',
-    callbackURL:  process.env.DOMAIN || '' + '/auth/facebook/callback'
+    callbackURL:  (process.env.DOMAIN || '') + '/auth/facebook/callback'
   },
 <% } if(filters.twitterAuth) { %>
   twitter: {
     consumerKey:     process.env.TWITTER_ID || 'id',
     consumerSecret: process.env.TWITTER_SECRET || 'secret',
-    callbackURL:  process.env.DOMAIN || '' + '/auth/twitter/callback'
+    callbackURL:  (process.env.DOMAIN || '') + '/auth/twitter/callback'
   },
 <% } if(filters.googleAuth) { %>
   google: {
     clientID:     process.env.GOOGLE_ID || 'id',
     clientSecret: process.env.GOOGLE_SECRET || 'secret',
-    callbackURL:  process.env.DOMAIN || '' + '/auth/google/callback'
+    callbackURL:  (process.env.DOMAIN || '') + '/auth/google/callback'
   }<% } %>
 };
 
 // Export the config object based on the NODE_ENV
 // ==============================================
 module.exports = _.merge(
   all,
-  require('./' + process.env.NODE_ENV + '.js') || {});
+  require('./' + process.env.NODE_ENV + '.js') || {});