- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

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

Add -H flag to print thread id.

Markup and wording fixes.

Approved by: re (blanket)

Document the '-i' option which allows the user to specify a ktr events
log file.

mdoc(7) fixes.

Add a "-r" flag to ktrdump(1) to print relative timestamps when used
with "-t" rather than absolute timestamps. This allows the reader
to get a better sense of latency between events, such as time to
schedule an interrupt thread from time the interrupt occurred. Assert
a copyright on ktrdump.c since I seem to be modifying it more than I
thought.

Add a quiet mode to ktrdump(1): if the "-q" flag is used, don't print
the pretty text header on top of the output. Simplifies feeding the
results of tracing into a script for mechanical processing.

The .Nm utility

mdoc(7) police: fixed typo, minor markup nits.

Add a man page.

Submitted by: davidc