Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Make example more correct (errstr is a pointer, not boolean).

Revert to r214147, errno is not clobbered as originally
thought.

Document strtonum()s behavior of setting errno to 0 when no error is found.

PR: docs/143330
Submitted by: Efstratios Karatzas (gpf dot kira at gmail dot com)
Discussed with: ru@
MFC after: 7 days

Sync with OpenBSD rev. 1.13:
strtonum does not require limits.h

Obtained from: OpenBSD
Discussed with: ru@
MFC after: 5 days

Revise markup in recently added manpages.

Add a non-optional newline after ".Bx".

Revert previous changes as we do support the .Ox macro for OpenBSD.

Pointed out by: ceri, ru, delphij

Fix HISTORY and point to OpenBSD.

Import of OpenBSD's strtonum(3) which is a nicer version of strtoll(3)
providing proper error checking and other improvements.

Obtained from: OpenBSD
Requested by: flz (to port Open[BGP|OSPF]D)
MFC after: 3 days