Ember - donation system, bans, loading screen & landing/index page

• Added Arma 3 support for server cards
• Added a favicon setting
• Added an optional custom sign in button
• Bug fixes & improvements

Files modified:

• web/app/Controllers/PagesController.php
• web/app/Models/Server.php
• web/bootstrap/app.php
• web/public/img/ember.ico
• web/public/js/forms.js
• web/resources/lang/en.php
• web/resources/views/admin/misc.twig
• web/resources/views/admin/servers.twig
• web/resources/views/layouts/navbar.twig
• web/resources/views/templates/app.twig