Draft: Add script used to import batches of pkgs from germinate files

Draft because it's maybe duplicate with other scripts we already have

./rebase-from-germinate -l sdk-keep.txt

requested review from @wlozano

assigned to @daissi

Thanks for the MR, I will use it to send some small batches of MR. As mentioned in !239 (merged) probably we should move to python-gitlab to improve consistency.