add html meta tags

site/_includes/top.html

@@ -5,6 +5,9 @@
   <title>{{ page.title }}</title>
   <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
   <meta name="viewport" content="width=device-width,initial-scale=1">
+  <meta name="author" content="Mahmoud Ben Hassine">
+  <meta name="description" content="XML-free open source java rules engine">
+  <meta name="keywords" content="java, rules engine, open source">
   <link href='http://fonts.googleapis.com/css?family=Lato:100,300,400,700,900,100italic,300italic,400italic,700italic,900italic' rel='stylesheet' type='text/css'>
   <link href='http://fonts.googleapis.com/css?family=Arizonia' rel='stylesheet' type='text/css'>
   <link rel="stylesheet" href="{{ site.url }}/css/normalize.css" />