Brings footer up to date

_includes/footer.html

@@ -2,7 +2,7 @@
   <data class="u-url" href="{{ "/" | relative_url }}"></data>
   <div class="wrapper">
     {%- assign module_parts = page.url | split: "/" -%}
-    {%- assign module_name = module_parts[2] | default: "index" -%}
+    {%- assign module_name = page.id | default: page.title -%}
     {%- assign navigation = site.data.navigation['modules'] -%}
     {%- assign module = navigation[module_name] -%}
     {%- if titles_size > 0 -%}