Fix: display user account details (#742).

When a User Account topic is revealed by clicking in the login-status pane its detail info is displayed in the detail panel.

REST Client:

one method has an additional `include_childs` parameter, boolean, optional. Default is `false`.
{{{
dm4c.restc.get_topic_by_value(key, value, include_childs)
}}}

The bug was introduced with DM 4.4 in conjunction with changed child topic loading.

Thanks to Malte for reporting!

Close #742.