Enable the "#include <QMultimedia>" camel-case header

Enable the "#include <QMultimedia>" camel-case header

Rename qtmedianamespace.h/cpp -> qmultimedia.h/cpp, and have
sync.profile generate the camel-case header during compilation.

Part of the Header Consistency Project
(http://lists.qt-project.org/pipermail/development/2012-October/007570.html)

Change-Id: Iade9ee6538970b4b9935f169eb2d9a0ea6949a95
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>