added webpack-encore for managing frontend assets #113 (#122)

* updated installation docu #113
* rewritten login page #113
* added icheck plugin #113
* changed to YesNoType in edit forms #113
* updated CONTRIBUTING.md #113
* added start of developer docu #113
* added compile scripts and compiled assets #113

templates/bundles/AvanzuAdminThemeBundle/Partials/_head.html.twig

@@ -1,12 +1,9 @@
 <meta charset="utf-8">
 <meta http-equiv="X-UA-Compatible" content="IE=edge">
 <meta content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no" name="viewport">
-<link rel="stylesheet" href="{{ asset('theme/bootstrap/css/bootstrap.min.css') }}">
-<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
-{#<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/ionicons/2.0.1/css/ionicons.min.css">#}
-<link rel="stylesheet" href="{{ asset('theme/dist/css/AdminLTE.min.css') }}">
-<link rel="stylesheet" href="{{ asset("theme/dist/css/skins/" ~ avanzu_admin_context.skin|default('skin-blue-light') ~ ".min.css") }}">
+<link rel="stylesheet" href="{{ asset('build/app.css') }}">
+<script src="{{ asset('build/app.js') }}"></script>
 <!--[if lt IE 9]>
 <script src="https://oss.maxcdn.com/html5shiv/3.7.3/html5shiv.min.js"></script>
 <script src="https://oss.maxcdn.com/respond/1.4.2/respond.min.js"></script>
-<![endif]-->
+<![endif]-->