MFC r267667:
use .Mt to mark up email addresses consistently (part1)

PR: 191174
Submitted by: Franco Fichtner <franco at lastsummer.de>

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

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

Mark up lkm with .Nm, since lkm is name of an api.

Submitted by: ru

Don't reference lkm(4), it doesn't exist.

PR: 108980
Submitted by: Yonatan

Bump a date in .Dd field. Last change brought some new functionality.

Spotted by: brueffer
Approved by: cognet (mentor)
MFC after: 1 week

Extend kldunload(8) functionality and fix minor problems:
o multiple modules can be unloaded at once (specified either by id or be
module name)
o exit with EX_USAGE after usage() is called.
o remove unused variables, since we keep command line flags as bitmask,
in 'opt'.
o 'kldload -n ...' does nothing. Add comment to this options.

Additionally:
o Update manual page to conform new functionality.
o Increace WARNS to 6. Because we can.

Approved by: cognet (mentor)
MFC after: 1 week

- Correctly spell MOD_QUIESCE
- use .Dv for it

MFC after: 3 days

Added the EXIT STATUS section where appropriate.

Scheduled mdoc(7) sweep.

Give kldunload a -f(orce) argument.

Add a MOD_QUIESCE event for modules. This should return error (EBUSY)
of the module is in use.

MOD_UNLOAD should now only fail if it is impossible (as opposed to
inconvenient) to unload the module. Valid reasons are memory references
into the module which cannot be tracked down and eliminated.

When kldunloading, we abandon if MOD_UNLOAD fails, and if -force is
not given, MOD_QUIESCE failing will also prevent the unload.

For backwards compatibility, we treat EOPNOTSUPP from MOD_QUIESCE as
success.

Document that modules should return EOPNOTSUPP for unknown events.

The .Nm utility

mdoc(7) police: removed HISTORY info from the .Os call.

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

Show that the -n option is optional

Suggested by: Bruce Evans <bde@zeta.org.au>
Reviewed by: dfr

Add cross-references to respective syscalls.

$Id$ -> $FreeBSD$

Fill-in the manpages a little.

Bitch if both an id and a name are specified. Make the man page and usage
message reflect this. As a bonus, make the -n optional so that 'kldunload
name' works as one would expect.

.Sh AUTHOR -> .Sh AUTHORS. Use .An/.Aq.

Sync. usage string and synopsis. Add rcsid.

a few code style changes:
o start function names in column 1
o sort order of flags in getopt and switch
o don't try to reference progname
o unspam some changes introduced by a 2.2.1-R build box instead of a
-current build box

doc changes:
o document when these commands first appeared
o put email address in angle brakets
o minor mdoc clean up

Add utilities for the kernel linker.