Add a signing policy.
$ sq-git policy describe
# OpenPGP policy file for git, version 0
## Commit Goodlist
## Authorizations
0. dvn
- may sign commits
- has OpenPGP cert: EC0ACCCA81CAA46BE40ECB79E1707CFFD7B85A02
1. dvzrv
- may sign commits
- has OpenPGP cert: 1793DAD5D803A8FFD7451697BB992F9864FAD168
2. justus
- may sign commits
- has OpenPGP cert: D2F2C5D45BE9FDE6A4EE0AAF31855247603831FD
3. justus-offline
- may sign commits
- may sign tags
- may sign archives
- may add users
- may retire users
- may goodlist commits
- has OpenPGP cert: CBCD8F030588653EEDD7E2659B7DD433F254904A
4. neal
- may sign commits
- has OpenPGP cert: F7173B3C7C685CD9ECC4191B74E445BA0E15C957
5. neal-offline
- may sign commits
- may sign tags
- may sign archives
- may add users
- may retire users
- may goodlist commits
- has OpenPGP cert: 8F17777118A33DDA9BA48E62AACB3243630052D9
6. wiktor-offline
- may sign commits
- may sign tags
- may sign archives
- may add users
- may retire users
- may goodlist commits
- has OpenPGP cert: 653909A2F0E37C106F5FAF546C8857E0D8E8F074
@dvn0, @dvzrv, @teythoon, @wiktor: Please ack that these are the right keys.