Styling workshops correctly.

1.  Use site.root for root path if set, otherwise use site.github.url.
2.  Display extra files for workshop-template repo as well as for lessons.

_includes/javascript.html

-<script src="{{ site.root }}/assets/js/jquery.min.js"></script>
-<script src="{{ site.root }}/assets/js/bootstrap.min.js"></script>
-<script src="{{ site.root }}/assets/js/lesson.js"></script>
+{% comment %}
+  If previewing locally, site.root is set in _config_dev.yml.
+  If site.root is not set, assume we're viewing on the web.
+{% endcomment %}
+{% if site.root %}
+  {% assign root = site.root %}
+{% else %}
+  {% assign root = site.github.url %}
+{% endif %}
+<script src="{{ root }}/assets/js/jquery.min.js"></script>
+<script src="{{ root }}/assets/js/bootstrap.min.js"></script>
+<script src="{{ root }}/assets/js/lesson.js"></script>

_includes/navbar.html

+{% comment %}
+  If previewing locally, site.root is set in _config_dev.yml.
+  If site.root is not set, assume we're viewing on the web.
+{% endcomment %}
+{% if site.root %}
+  {% assign root = site.root %}
+{% else %}
+  {% assign root = site.github.url %}
+{% endif %}
 <nav class="navbar navbar-default">
   <div class="container-fluid">
     <div class="navbar-header">
@@ -7,49 +16,64 @@
         <span class="icon-bar"></span>
         <span class="icon-bar"></span>
       </button>
+
+      {% comment %} Select what logo to display. {% endcomment %}
       {% if page.carpentry == "swc" %}
       <a href="{{ site.swc_site }}" class="pull-left">
-        <img class="navbar-logo" src="{{ site.root }}/assets/img/swc-icon-blue.svg" alt="Software Carpentry logo" />
+        <img class="navbar-logo" src="{{ root }}/assets/img/swc-icon-blue.svg" alt="Software Carpentry logo" />
       </a>
       {% elsif page.carpentry == "dc" %}
       <a href="{{ site.dc_site }}" class="pull-left">
-        <img class="navbar-logo" src="{{ site.root }}/assets/img/dc-icon-black.svg" alt="Data Carpentry logo" />
+        <img class="navbar-logo" src="{{ root }}/assets/img/dc-icon-black.svg" alt="Data Carpentry logo" />
       </a>
       {% elsif site.carpentry == "swc" %}
       <a href="{{ site.swc_site }}" class="pull-left">
-        <img class="navbar-logo" src="{{ site.root }}/assets/img/swc-icon-blue.svg" alt="Software Carpentry logo" />
+        <img class="navbar-logo" src="{{ root }}/assets/img/swc-icon-blue.svg" alt="Software Carpentry logo" />
       </a>
       {% elsif site.carpentry == "dc" %}
       <a href="{{ site.dc_site }}" class="pull-left">
-        <img class="navbar-logo" src="{{ site.root }}/assets/img/dc-icon-black.svg" alt="Data Carpentry logo" />
+        <img class="navbar-logo" src="{{ root }}/assets/img/dc-icon-black.svg" alt="Data Carpentry logo" />
       </a>
       {% endif %}
-      <a class="navbar-brand" href="{{ site.root }}/">Home</a>
+
+      {% comment %} Always show link to home page. {% endcomment %}
+      <a class="navbar-brand" href="{{ root }}/">Home</a>
+
     </div>
     <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
       <ul class="nav navbar-nav">
-        <li><a href="{{ site.root }}/conduct/">Code of Conduct</a></li>
+
+	{% comment %} Always show code of conduct. {% endcomment %}
+        <li><a href="{{ root }}/conduct/">Code of Conduct</a></li>
+
+	{% comment %} Show setup instructions, reference guide, and lesson episodes for lessons. {% endcomment %}
         {% if site.kind == "lesson" %}
-        <li><a href="{{ site.root }}/setup/">Setup</a></li>
+        <li><a href="{{ root }}/setup/">Setup</a></li>
+        <li><a href="{{ root }}/reference/">Reference</a></li>
         <li class="dropdown">
-          <a href="{{ site.root }}/" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">Episodes <span class="caret"></span></a>
+          <a href="{{ root }}/" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">Episodes <span class="caret"></span></a>
           <ul class="dropdown-menu">
             {% for episode in site.episodes %}
-            <li><a href="{{ site.root }}{{ episode.url }}">{{ episode.title }}</a></li>
+            <li><a href="{{ root }}{{ episode.url }}">{{ episode.title }}</a></li>
             {% endfor %}
           </ul>
         </li>
+	{% endif %}
+
+	{% comment %} Show extras for lessons or if this is the main workshop-template repo (where they contain documentation). {% endcomment %}
+	{% if site.kind == "lesson" or site.repository_name == "workshop-template" %}
         <li class="dropdown">
-          <a href="{{ site.root }}/" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">Extras <span class="caret"></span></a>
+          <a href="{{ root }}/" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">Extras <span class="caret"></span></a>
           <ul class="dropdown-menu">
             {% for extra in site.extras %}
-            <li><a href="{{ site.root }}{{ extra.url }}">{{ extra.title }}</a></li>
+            <li><a href="{{ root }}{{ extra.url }}">{{ extra.title }}</a></li>
             {% endfor %}
           </ul>
         </li>
-        <li><a href="{{ site.root }}/reference/">Reference</a></li>
-        {% endif %}
-        <li><a href="{{ site.root }}/license/">License</a></li>
+	{% endif %}
+
+	{% comment %} Always show license. {% endcomment %}
+        <li><a href="{{ root }}/license/">License</a></li>
       </ul>
       <form class="navbar-form navbar-right" role="search" id="search" onsubmit="google_search(); return false;">
         <div class="form-group">

_layouts/workshop.html

 ---
 ---
+{% comment %}
+  If previewing locally, site.root is set in _config_dev.yml.
+  If site.root is not set, assume we're viewing on the web.
+{% endcomment %}
+{% if site.root %}
+  {% assign root = site.root %}
+{% else %}
+  {% assign root = site.github.url %}
+{% endif %}
 <!doctype html>
 <html lang="en">
   <head>
@@ -25,9 +34,9 @@
     <meta http-equiv="X-UA-Compatible" content="IE=edge">
     <meta http-equiv="last-modified" content="{{ site.time }}">
     <meta name="viewport" content="width=device-width, initial-scale=1">
-    <link rel="stylesheet" type="text/css" href="{{ site.root }}/assets/css/bootstrap.css" />
-    <link rel="stylesheet" type="text/css" href="{{ site.root }}/assets/css/bootstrap-theme.css" />
-    <link rel="stylesheet" type="text/css" href="{{ site.root }}/assets/css/lesson.css" />
+    <link rel="stylesheet" type="text/css" href="{{ root }}/assets/css/bootstrap.css" />
+    <link rel="stylesheet" type="text/css" href="{{ root }}/assets/css/bootstrap-theme.css" />
+    <link rel="stylesheet" type="text/css" href="{{ root }}/assets/css/lesson.css" />
     {% if site.carpentry == "swc" %}
     <link rel="shortcut icon" type="image/x-icon" href="/favicon-swc.ico" />
     {% endif %}