Access Control: hide password topics (#375).

The Webclient do not display Password topics, neither in the detail panel nor on the canvas.
The only situation a password appears (in the detail panel) is when editing an User Account.

You must reset the DB.

BREAKING CHANGES

Webclient: the RendererHelper's topic_list() function does not render hidden topics.
That are topics whose type's view configuration have a hidden=true setting.

Webclient: the TopicType model class has a is_hidden() function.

See ticket 375.