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

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

Expand *n't contractions.

Sort sections.

Uniformly refer to a file system as "file system".

Approved by: re

The .Nm utility

mdoc(7) police: sort SEE ALSO xrefs (sort -b -f +2 -3 +1 -2).

mdoc(7) police: use the new features of the Nm macro.

Remove more single-space hard sentence breaks.

Remove single-space hard sentence breaks. These degrade the quality
of the typeset output, tend to make diffs harder to read and provide
bad examples for new-comers to mdoc.

This is another in Martin Blapp's N-series of mount-related cleanups :)
Changes are:
- rpc.umntall is called at the right places now in /etc/rc*
- rpc.umntall timeout has been lowered from two days (too high) to one
- verbose messages in rpc.umntall have been clarified
- kill double entries in /var/db/mounttab when rpc.umntall is invoked
- ${early_nfs_mounts} has been removed from /etc/rc
- patched mount(8) -p to print different pass/dump values for ufs filesystems.
(last patch recieved from dan <bugg@bugg.strangled.net>)

Submitted by: Martin Blapp <mbr@imp.ch>, dan <bugg@bugg.strangled.net>

mdoc(7)'fy
sort XREFs

Fix errors unmounting remote systems which don't understand RPC_UMNTALL.

Submitted by: Martin Blapp <mblapp@kassiopeja.lan.attic.ch>

Add rpc.umntall utility, to be used by startup and shutdown scripts
to replace (broken) umntall signal code previously in mountd.

Submitted by: Martin Blapp <mb@imp.ch>