nixos/fcgiwrap: add option migration instruction errors

This adds migration instructions for the removed global shared instance
configuration of fcgiwrap.

Adding those explicit messages to the previous options requires moving
the newly defined options from `services.fcgiwrap.*` to
`services.fcgiwrap.instances.*` due to an option namespace clash.

`mkRenamedOptionModule` was not used because the previous options do
not directly map to the new ones. In particular, `user` and `group`
were described as setting the socket's permission, but were actually
setting the process' running user.

Co-authored-by: Minijackson <minijackson@riseup.net>

0 files changed, 0 insertions, 0 deletions