QtIFW

Include application size only in case of installer.

When createLocalRepository option was specified,
include the size of application only for the
very first installation (isInstaller()) and
omit it in other cases.

Change-Id: I3bb248cb1436c16e570140e8d70ebf5cba2c37e5
Reviewed-by: Christoph Vogtländer <c.vogtlaender@sigma-surface-science.com>
Reviewed-by: Kai Koehne <kai.koehne@theqtcompany.com>