You may find yourself in a situation where you have a modified v2_key.dev, and are missing a v2_key.
that is easy to fix:
mv v2_key.dev v2_key
git checkout v2_key.devIf you are checking out an older branch, it may complain that you need to remove certs/v2_key in order to change to another branch.
mv certs/v2_key certs/v2_key.bak
git checkout <branch>
git rebase upstream/master
mv certs/v2_key.bak certs/v2_key