Add a stub modules to compile on Windows

It is the first commit which prepares possibility of build for Windows;
still there is no Windows-specific implementation of bluetooth classes.

Tested build with Qt5 (MinGW).

Change-Id: I70d8c5cff4ac4e8b9192ab8556d81aad8432394a
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>