Removed the TabBar

Now the switching between the home and the settings is done
with the appBar. In the app bar there are social network buttons,
the home button and the settings button.

Droped the view Main and renamed the controller Social in AppBar.
Reintroduced the info button

The info button was needed in the library section.
Changed from 'social' icon to 'more' icon for the appbar button.
Better home icons spacing; removed Settings titlebar
Refactored Mensa; new prototype

The Mensa section is going to use a webcam to allow the users
to check the queue length.
Right now a temporary picture is used. When there is no connection
a warning picture is set to inform the user.
Renamed MenuMensa to MensaMenu as more views are probably going
to be added to the Mensa section.
Refactor 1: Home page as list

The home page is now shown as list.
The controller Home loads all the views in the new Home list.
The loading mask uses a spinner instead of the text.
Better localising mechanism

The NavigationBar.setTitle and the backButton.setText have been
overwritten to improve the language setting mechanism.