API SSO, Beautification of Tables, and more. (#562)

# One Thousandth Commit 🎉 🎈 🎆 🍾

* Allow requiring API ownership validation by SSO.
Closes #163

* Add Discourse group name length restrictions.

* Redirect after api addition/deletion of main character

* Correct admin searching for removed discourse_username field in AuthServicesInfo

* Correct admin function to sync user Discourse groups

* Beautify tables by removing borders and hiding when empty.

*Add buttons on dead-end pages to return to originating view.

stock/templates/registered/srpfleetdata.html

@@ -34,7 +34,8 @@
                     <b>{% trans "Total ISK Cost:" %} {{ totalcost | intcomma }}</b>
                 </div>
             </div>
-            <table class="table table-bordered">
+            {% if srpfleetrequests %}
+            <table class="table">
                 <tr>
                     <th class="text-center">{% trans "Pilot Name" %}</th>
                     <th class="text-center">{% trans "Killboard Link" %}</th>
@@ -120,6 +121,9 @@
                     </tr>
                 {% endfor %}
             </table>
+            {% else %}
+            <div class="alert alert-warning text-center">No SRP requests for this fleet.</div>
+            {% endif %}
         </div>
     </div>