Doc: Fix module names in .qdocconf for Qt Multimedia & Widgets

This change fixes QCH documentation title for Qt Multimedia Widgets.
Also, the project names are changed to use CamelCase - this is required
as qdoc will generate visible output (tags in example manifest files)
based on those names.

Also, removes documentation topic for QML types from Qt Multimedia
Widgets as it doesn't have any.

Change-Id: Ic5f3b7a3094a1012f3c356f0195a8eb40d9d9e35
Reviewed-by: Jerome Pasion <jerome.pasion@digia.com>