add view osusers.views.AddSshPublicKey

- implement new form osusers.forms.AddSshPublicKeyForm
- move message texts from osusers.admin to osusers.forms
- add new view osusers.views.AddSshPublicKey
- add new URL patter 'add_ssh_key' to osusers.urls
- add new template osusers/sshpublickey_create.html
- link from hosting package detail template to 'add_ssh_key'
- add changelog entry for new feature

gnuviechadmin/templates/hostingpackages/customerhostingpackage_detail.html

@@ -68,6 +68,7 @@
       <ul class="list-group">
         <li class="list-group-item"><a href="#" title="{% trans "Edit Hosting Package Description" %}">{% trans "Edit description" %}</a></li>
         <li class="list-group-item"><a href="{% url "set_osuser_password" slug=osuser.username %}">{% if osuser.is_sftp_user %}{% trans "Set SFTP password" %}{% else %}{% trans "Set SSH/SFTP password" %}{% endif %}</a></li>
+        <li class="list-group-item"><a href="{% url "add_ssh_key" package=hostingpackage.id %}" title="{% blocktrans %}Add an SSH public key that can be used as an alternative for password{% endblocktrans %}">{% trans "Add SSH public key" %}</a></li>
       </ul>
     </div>
   </div>