Updating the docs to match latest skywater-pdk.

Taken from https://github.com/google/skywater-pdk
```
commit b5ff6174d9aa921f670f12a2893969fe4a516f6c (HEAD -> main, upstream/main)
Merge: 5e159bd 73e9c84
Author: Tim Ansell <me@mith.ro>
Date:   Tue Nov 2 13:28:11 2021 -0700

    Merge pull request #341 from mithro/sphinx-theme-fix

    Update the sphinx theme
```

Signed-off-by: Tim 'mithro' Ansell <tansell@google.com>
diff --git a/docs/_templates/relbar.html b/docs/_templates/relbar.html
new file mode 100644
index 0000000..d693e3e
--- /dev/null
+++ b/docs/_templates/relbar.html
@@ -0,0 +1,13 @@
+{% extends '!relbar.html' %}
+
+{%- block extralinks -%}
+{{ super() }}
+
+<li class="md-tabs__item"><a href="https://www.skywatertechnology.com/" class="md-tabs__link"><i class="md-icon">business</i> SkyWater</a></li>
+<li class="md-tabs__item"><a href="https://efabless.com/open_shuttle_program" class="md-tabs__link"><i class="md-icon">precision_manufacturing</i> Shuttle Program</a></li>
+<li class="md-tabs__item"><a href="https://join.skywater.tools/" class="md-tabs__link"><i class="md-icon">chat_bubble</i> Chat</a></li>
+<li class="md-tabs__item"><a href="https://groups.google.com/g/skywater-pdk-users" class="md-tabs__link"><i class="md-icon">campaign</i>Announcements</a></li>
+<li class="md-tabs__item"><a href="https://groups.google.com/g/skywater-pdk-users" class="md-tabs__link"><i class="md-icon">mail</i> Mailing List</a></li>
+
+
+{%- endblock -%}