Rename admin users controller/route

Started out as a simple helper page to list LDAP users, but turning into
proper user management now.

app/views/admin/users/index.html.erb

@@ -0,0 +1,54 @@
+<%= render HeaderComponent.new(title: "Users: #{@ou}") %>
+
+<%= render MainSimpleComponent.new do %>
+  <section>
+    <%= render QuickstatsContainerComponent.new do %>
+      <%= render QuickstatsItemComponent.new(
+          type: :number,
+          title: 'Confirmed',
+          value: @stats[:users_confirmed],
+      ) %>
+      <%= render QuickstatsItemComponent.new(
+          type: :number,
+          title: 'Pending',
+          value: @stats[:users_pending],
+      ) %>
+    <% end %>
+  </section>
+
+  <% if @orgs.length > 1 %>
+    <section>
+      <h3 class="hidden">Domains</h3>
+      <ul>
+        <% @orgs.each do |org| %>
+          <li class="inline-block">
+            <%= link_to org[:ou], admin_users_path(ou: org[:ou]), class: "ks-text-link" %>
+          </li>
+        <% end %>
+      </ul>
+    </section>
+  <% end %>
+
+  <section>
+    <table>
+      <thead>
+        <tr>
+          <th>UID</th>
+          <th>E-Mail</th>
+          <th>Admin</th>
+          <!-- <th>Password</th> -->
+        </tr>
+      </thead>
+      <tbody>
+        <% @entries.each do |entry| %>
+        <tr>
+          <td><%= entry[:uid] %></td>
+          <td><%= entry[:mail] %></td>
+          <td><%= entry[:admin] %></td>
+          <!-- <td><%= entry[:password] %></td> -->
+        </tr>
+        <% end %>
+      </tbody>
+    </table>
+  </section>
+<% end %>