Add support for NFC file and data sharing

Provide ability to allow NFC enabled devices to exchange file and data content
using a high-level API.

[ChangeLog][QtNfc][General] A new NFC share API was added.
The API provides sharing of NDEF messages and arbitrary files via
NFC and may potentially use other communication protocols
such as wifi or Bluetooth as part of its implementation.

Change-Id: I878df1702ce4164384096d00e53dcd354d1bfafc
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>
Reviewed-by: Fabian Bumberger <fbumberger@rim.com>