add source version

_layouts/default.html

@@ -19,6 +19,7 @@
       <h1 class="project-name">{{ page.title | default: site.title | default: site.github.repository_name }}</h1>
       <h2 class="project-tagline">{{ page.description | default: site.description | default: site.github.project_tagline }}</h2>
       <a href="/view/" class="btn">RESTART</a>
+      <a href="/view/test.html" class="btn">Source Version</a>
       {% if site.github.is_project_page %}
         <a href="{{ site.github.repository_url }}" class="btn">View on GitHub</a>
       {% endif %}