Add authentication from upstream providers (#107)

Let BasicOIDC delegate authentication to upstream providers (Google, GitHub, GitLab, Keycloak...)

Reviewed-on: #107

templates/settings/account_details.html

@@ -5,27 +5,27 @@
     <tbody>
     <tr>
         <th scope="row">User ID</th>
-        <td>{{ u.uid.0 }}</td>
+        <td>{{ _p.user.uid.0 }}</td>
     </tr>
     <tr>
         <th scope="row">First name</th>
-        <td>{{ u.first_name }}</td>
+        <td>{{ _p.user.first_name }}</td>
     </tr>
     <tr>
         <th scope="row">Last name</th>
-        <td>{{ u.last_name }}</td>
+        <td>{{ _p.user.last_name }}</td>
     </tr>
     <tr>
         <th scope="row">Username</th>
-        <td>{{ u.username }}</td>
+        <td>{{ _p.user.username }}</td>
     </tr>
     <tr>
         <th scope="row">Email</th>
-        <td>{{ u.email }}</td>
+        <td>{{ _p.user.email }}</td>
     </tr>
     <tr>
         <th scope="row">Account type</th>
-        <td>{% if u.admin %}Admin{% else %}Regular user{% endif %}</td>
+        <td>{% if _p.user.admin %}Admin{% else %}Regular user{% endif %}</td>
     </tr>
     </tbody>
 </table>