Introduced some basic metadata information

Change-Id: I4fab9d39a86200637cd780ba293e9982f4f0724b
diff --git a/templates/layouts/main.html.ep b/templates/layouts/main.html.ep
index ab50acf..5f9983c 100644
--- a/templates/layouts/main.html.ep
+++ b/templates/layouts/main.html.ep
@@ -1,9 +1,45 @@
 <!DOCTYPE html>
-<html>
-  <head>
+% my $lang = app->localize->preference // 'en';
+% my $desc = loc('korap_desc');
+% my $keywords = loc('korap_keywords');
+<html lang="<%= $lang %>" xml:lang="<%= $lang %>" xmlns="http://www.w3.org/1999/xhtml" xmlns:og="http://opengraphprotocol.org/schema/">
+  <head prefix="og: http://ogp.me/ns# website: http://ogp.me/ns/website#">
     <title><%= title() // loc('korap_desc') %></title>
     <meta charset="utf-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0, user-scalable=false, user-scalable=no" />
+    <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1" />
+    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
+    <meta http-equiv="Content-Style-Type" content="text/css" />
+    <meta http-equiv="Content-Script-Type" content="text/javascript" />
+    <meta name="msapplication-TileImage" content="<%= url_for '/img/windows-tile.png' %>" />
+    <meta name="msapplication-TileColor" content="#9bad0b" />
+    <meta name="robots" content="index,follow" />
+    <meta name="apple-mobile-web-app-status-bar-style" content="default" />
+    <meta name="description" content="<%= $desc %>" />
+    <meta name="language" content="<%= $lang %>" />
+    <meta name="author" content="The KorAP Team" />
+    <meta name="DC.type" content="service" />
+    <meta name="DC.creator" content="IDS Mannheim" />
+    <meta name="DC.title" content="<%= title() || loc('korap_short') %>" />
+    <meta name="DC.description" content="<%= $desc %>" />
+    <meta name="DC.format" content="text/html" />
+    <meta name="DC.contributor" content="The KorAP Team" />
+    <meta name="DC.publisher" content="IDS Mannheim" />
+    <meta name="DC.language" content="<%= $lang %>" />
+    <meta property="og:url" content="<%= url_for->to_abs %>" />
+    <meta property="og:locale" content="<%= $lang %>" />
+    <meta property="og:description" content="<%= $desc %>" />
+    <meta property="og:image" content="<%= url_for '/img/korap-200.png' %>" />
+    <meta property="og:image:width" content="200" />
+    <meta property="og:image:height" content="200" />
+    <meta name="twitter:image" content="<%= url_for '/img/korap-280.png' %>" />
+    <meta name="twitter:description" content="<%= $desc %>" />
+    <meta name="geo.region" content="<%= loc 'korap_region' %>" />
+    <meta name="geo.placename" content="<%= loc 'korap_placename' %>" />
+    <meta name="keywords" content="<%= $keywords %>" />
+    <meta name="DC.subject" content="<%= $keywords %>" />
+
+    <link rel="apple-touch-icon" href="<%= url_for '/img/apple-touch-icon.png' %>" />
     <link href="<%= stash 'prefix' %>/favicon.ico" rel="shortcut icon" type="image/x-icon" /> 
     <link href="<%= stash 'prefix' %>/css/kalamar-<%= $Kalamar::VERSION %>.css" type="text/css" rel="stylesheet" />
 %= javascript begin  
@@ -21,7 +57,7 @@
   </head>
 % my $embedded = 0;
 % $embedded = 1 if stash('embedded');
-  <body class="no-js<% if ($embedded) { %> embedded<% } %>">
+  <body class="no-js<% if ($embedded) { %> embedded<% } %>" itemscope itemtype="http://schema.org/<%= stash('schematype') || 'WebApplication' %>">
     <script>document.body.classList.remove('no-js');</script>
     <div id="kalamar-bg"></div>