Add a setting for customizing the app title

the app title is inserted into the <title> of all tepmlates

src/node/utils/Settings.js

@@ -29,6 +29,11 @@ var vm = require('vm');
 /* Root path of the installation */
 exports.root = path.normalize(path.join(npm.dir, ".."));
 
+/**
+ * The app title, visible e.g. in the browser window
+ */
+exports.title = "Etherpad Lite";
+
 /**
  * The IP ep-lite should listen to
  */