fixup! Attach environment to commit
fixup! Add env-set pmctl command
fixup! Add env-set pmctl command
Add "env-get" pmctl to list environment variables

Reads the environment variables stored in the strong-pm server. If
given, the pmctl client filters the list by name.
fixup! Add "env-get" pmctl to list environment variables
fixup! Add env-set pmctl command
fixup! Add "env-get" pmctl to list environment variables
fixup! Add env-set pmctl command
Add env-unset command to pmctl

Internally add null as a special value for environment variables that
indicates deletion.

Expose this convention on the CLI as `sl-pmctl env-unset KEYS...`