Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

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

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

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

mdoc: convert .Fd to .In, which is much nicer.

Remove contractions.

Globally replace u_int*_t from (non-contributed) man pages.

The reasoning behind this, is that if we are consistent in our
documentation about the uint*_t stuff, people will be less tempted to
write new code that uses the non-standard types.

I am not going to bump the man page dates, as these changes can be
considered style nits. The meaning of the man pages is unaffected.

MFC after: 1 month

Synchronize with laster version of m4 from OpenBSD and NetBSD
This bring better compatibility with gnum4

Reviewed by: cognet
Approved by: cognet
Obtained from: OpenBSD, NetBSD