-added links to Dialogs, Styles, and Layouts landing pages.
-added section about the NFC, Bluetooth, and Positioning modules.

Task-number: QTBUG-33360
Change-Id: Ia238eda34f4055ba6b2a52135f788b480512fd74
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>