Previous iteration of this assumed that these won't fail because we've
already setup the jail param to this point, but the allocations could still
fail in pretty bad conditions.
Admit that it's possible and return (ENOENT, EINVAL, ENOMEM, or 0) when
deleting arguments. EINVAL shouldn't happen since we're passing optarg;
which may satisfy *optarg == '\0' but never optarg == NULL.
CID: 1394885, 1394901
- Support passing arbitrary jail arguments via -o
- Split the related (and rewritten since the GSoC) jail bits out into a new
bectl_jail.c file, to reduce clutter in bectl.c
- Don't use RFC 1918 IP space [0]; we'll instead set no default IPv4 and let
the user pass in any address options they wish via -o
Reported by: rgrimes [0], Shawn Webb [0]
