fix hostOSVersion for other platforms than Windows or OS X

Change-Id: I84ee85506d24ebeb9e801f684495f9200cb759f6
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>
Make MSI files executable with the run command.

Task-number: QBS-423

Change-Id: If7c13bc5452a2a8b9c898f3aefe8b8986f4bab92
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>