Remove references of QML as a 'declarative' language

Though the core of QML is declarative, it incorporates JavaScript, a
multi-paradigm language on its own. It's therefore correct to call it
a multi-paradigm language, too.

Change-Id: Ia72acedafefb68ea8c49b9f6ab195ca9e73dad5f
Reviewed-by: hjk <hjk121@nokiamail.com>
Reviewed-by: Sze Howe Koh <szehowe.koh@gmail.com>
Reviewed-by: Christopher Adams <chris.adams@jollamobile.com>
Reviewed-by: Lars Knoll <lars.knoll@digia.com>