Modules admin page is too long (groups open by default)

Problem / Motivation

The module page is too long to easilly navigate throught. One has to scroll down and / or toggle close each Module groups in order to have a global vision of the whole list.

Module groups should be closed by default.

Users then can choose to open / close each groups whom (s)he wants to see the full list of modules.

Proposed solution

The ModuleListForm class should present closed groups by default, as proposed in the attached patch.