How to cite (ProjectPythia#418)

* add website to authors

* add doi back

* Update footer-menu.html

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: jukent

_templates/footer-menu.html

@@ -1,3 +1,4 @@
+{% set ext_icon = '<i class="fas fa-external-link-alt"></i>' %}
 <div class="container-fluid footer-menu pt-4">
   <div class="container">
     <div class="row justify-content-center">
@@ -20,6 +21,11 @@ <h1>{{ _("About") }}</h1>
               >{{ _("The Project Team") }}</a
             >
           </li>
+          <li>
+            <a href="https://projectpythia.org/#how-to-cite"
+              >{{ _("How to Cite") }}</a
+            >
+          </li>
         </ul>
       </div>
       <div class="col-9 col-sm-4 col-md-4 col-lg-3 footer-menu-col">
@@ -29,15 +35,8 @@ <h1>{{ _("Give Feedback") }}</h1>
             <a href="mailto:[email protected]">{{ _("Email us!") }}</a>
           </li>
           <li>
-            <a
-              href="https://github.com/ProjectPythia/projectpythia.github.io/discussions"
-              >{{ _("Project Pythia Discussions") }}</a
-            >
-          </li>
-          <li>
-            <a
-              href="https://github.com/ProjectPythia/pythia-foundations/discussions"
-              >{{ _("Pythia Foundations Discussions") }}</a
+            <a href="https://discourse.pangeo.io/c/education/project-pythia/60s"
+              >{{ _("Pangeo Discourse") }}</a
             >
           </li>
         </ul>
@@ -50,12 +49,6 @@ <h1>{{ _("Contribute") }}</h1>
               >{{ _("How to contribute to Project Pythia") }}</a
             >
           </li>
-          <li>
-            <a
-              href="https://foundations.projectpythia.org/appendix/how-to-contribute.html"
-              >{{ _("How to contribute to Pythia Foundations") }}</a
-            >
-          </li>
           <li>
             <a href="https://projectpythia.org/code_of_conduct.html"
               >{{ _("Our code of conduct") }}</a