WIP: currently just a simple setup that creates an empty git repo if
it doesn’t exist yet, and writes a commit to it.
A simple database backed by a bare git repository.
WIP: Will speak a simple interactive protocol to query files and
update them atomically.
It could be made atomic on the git repo level, if a lock is taken
between reading the current commit ref and creating the commit.
Change-Id: I1fd30a046ac977063c3e08c36d96e835b35ff07d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/3046
Tested-by: BuildkiteCI
Reviewed-by: Profpatsch <mail@profpatsch.de>
