QtIFW

Store installer data in a separate file on Mac to support code signing

Code signing fails on Mac OS X if there's any extra data after the
link edit segment in a binary, so store the installer data in a separate
file inside the bundle.

Task-number: QTIFW-153
Change-Id: Ie1edf21212b4a3bc5b6f32eea3f5d61e8800a0d5
Reviewed-by: Karsten Heimrich <karsten.heimrich@digia.com>
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Reviewed-by: Simo Fält <simo.falt@digia.com>
Reviewed-by: Niels Weber <niels.weber@digia.com>