Automatic version number bump feature for installer components

To ease testing snapshots from online repository the version number
of the components should get increased automatically in order for the
users to get updates via the Updater. I.e. promoting updates.

Use special tag '%VERSION_NUMBER_AUTO_INCREASE%' in package.xml files
as a place holder for version number bump.

The create_installer.py must be called with:
'--force-version-number-increase' to enable this feature. Otherwise
the value of '%VERSION_NUMBER_AUTO_INCREASE%' will be set empty i.e.
no effect. If feature enabled then a time stamp based number is
generated as the value which should ensure the version number bump
always.

release_build_handler.py triggers this feature if:

1) update staging repository is True
2) updating production repository is False

i.e. making sure that the forced version number bump will not end up
in production.

Change-Id: I1d18d73837cd14ed9152ec10c05cd3f1ad67271f
Reviewed-by: Samuli Piippo <samuli.piippo@digia.com>
Reviewed-by: Sergio Ahumada <sahumada@blackberry.com>