added page title

_includes/head.html

@@ -2,7 +2,7 @@
   <meta charset="utf-8">
   <meta http-equiv="X-UA-Compatible" content="IE=edge">
   <meta name="viewport" content="width=device-width, initial-scale=1">
-  <!-- link rel="stylesheet" href="{{ "/assets/main.css" | relative_url }}"-->
+  <title>{{ site.title }}{% if page.title %} - {{ page.title }}{% endif %}</title>
   {%- asset styles.css -%}
   {%- feed_meta -%}
   {%- if jekyll.environment == 'production' and site.google_analytics -%}