Figure out how could we use git submodules from openSUSE Factory pool

[davidcassany]

As an alternative to OBS links from Factory, for a git based OBS project we could simply set git submodules to the packages we aim to link.

I did a quick test and failed for some unknown issue, I could not define a git submodule from http://src.opensuse.org/pool/. I have the feeling there might be some LSF issue around submodules.

This is to investigate it further or even figuring out alternatives to a git submodule.