Various layout fixes and enhancement

Closes #82 (closed), #84 (closed), #85 (closed), #107 (closed) and other improvements

issue	before	after
Doublon du bloc action dans les détails des pro... (#82 - closed)
top bar (en haut) et side nav (à gauche) : clar... (#84 - closed)
service details & profil details : empêcher le ... (#85 - closed)
absence de wrap sur les token (#107 - closed)

hiboo/templates/sidebar.html

+<li class="nav-item">
+  <a class="nav-link">
+    <i class="nav-icon fas fa-moon"></i>
+    <p>{% trans %}Dark theme{% endtrans %}</p>
+      <label class="theme-switch ml-3" for="checkbox">
+        <input type="checkbox" id="checkbox">
+        <span class="slider round"></span>
+      </label>
+  </a>
+</li>
+
 {% if current_user.is_authenticated %}
 <li class="nav-header">{% trans %}Account{% endtrans %}</li>
 <li class="nav-item">
@@ -25,11 +36,6 @@
     <i class="nav-icon fas fa-qrcode"></i> <p>{% trans %}Two-factor authentication{% endtrans %}</p>
   </a>
 </li>
-<li class="nav-item">
-  <a class="nav-link" href="{{ url_for("account.signout") }}">
-    <i class="nav-icon fas fa-sign-out-alt"></i> <p>{% trans %}Sign out{% endtrans %}</p>
-  </a>
-</li>
 {% else %}
 <li class="nav-item">
   <a class="nav-link" href="{{ utils.url_for("account.signup") }}">
@@ -78,3 +84,12 @@
     <i class="nav-icon fas fa-book"></i> <p>{% trans %}Admin guide{% endtrans %}</p>
   </a>
 </li>
+
+{% if current_user.is_authenticated %}
+<li class="nav-header"></li>
+<li class="nav-item">
+  <a class="nav-link border" href="{{ url_for("account.signout") }}">
+    <i class="nav-icon fas fa-power-off"></i> <p>{% trans %}Sign out{% endtrans %}</p>
+  </a>
+</li>
+{% endif %}