Adding search engine friendly sitemap

sitemap.xml

@@ -0,0 +1,56 @@
+---
+layout: null
+sitemap:
+  exclude: 'yes'
+---
+<?xml version="1.0" encoding="UTF-8"?>
+<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
+  {% for post in site.posts %}
+    {% unless post.published == false %}
+    <url>
+      <loc>{{ site.url }}{{ post.url }}</loc>
+      {% if post.sitemap.lastmod %}
+        <lastmod>{{ post.sitemap.lastmod | date: "%Y-%m-%d" }}</lastmod>
+      {% elsif post.date %}
+        <lastmod>{{ post.date | date_to_xmlschema }}</lastmod>
+      {% else %}
+        <lastmod>{{ site.time | date_to_xmlschema }}</lastmod>
+      {% endif %}
+      {% if post.sitemap.changefreq %}
+        <changefreq>{{ post.sitemap.changefreq }}</changefreq>
+      {% else %}
+        <changefreq>monthly</changefreq>
+      {% endif %}
+      {% if post.sitemap.priority %}
+        <priority>{{ post.sitemap.priority }}</priority>
+      {% else %}
+        <priority>0.5</priority>
+      {% endif %}
+    </url>
+    {% endunless %}
+  {% endfor %}
+  {% for page in site.pages %}
+    {% unless page.sitemap.exclude == "yes" or page.name == "feed.xml" %}
+    <url>
+      <loc>{{ site.url }}{{ page.url | remove: "index.html" }}</loc>
+      {% if page.sitemap.lastmod %}
+        <lastmod>{{ page.sitemap.lastmod | date: "%Y-%m-%d" }}</lastmod>
+      {% elsif page.date %}
+        <lastmod>{{ page.date | date_to_xmlschema }}</lastmod>
+      {% else %}
+        <lastmod>{{ site.time | date_to_xmlschema }}</lastmod>
+      {% endif %}
+      {% if page.sitemap.changefreq %}
+        <changefreq>{{ page.sitemap.changefreq }}</changefreq>
+      {% else %}
+        <changefreq>monthly</changefreq>
+      {% endif %}
+      {% if page.sitemap.priority %}
+        <priority>{{ page.sitemap.priority }}</priority>
+      {% else %}
+        <priority>0.3</priority>
+      {% endif %}
+    </url>
+    {% endunless %}
+  {% endfor %}
+</urlset>