Hello Guix devs,

This patch to GNU Shepherd removes the hard-coded respawn limit and
makes it a configurable option.
The respawn limit works generally the same way as before, allowing N
respawns in M seconds:

#:respawn-limit '(N . M)

We can disable respawns by setting N to 0, which will abort the service
after the first crash. Likewise, we can always respawn by setting

#:respawn-limit #f


Sincerely,
Ryan Sundberg