- Copy stable/10@285827 to releng/10.2 in preparation for 10.2-RC1
builds.
- Update newvers.sh to reflect RC1.
- Update __FreeBSD_version to reflect 10.2.
- Update default pkg(8) configuration to use the quarterly branch.[1]

Discussed with: re, portmgr [1]
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

Hide the implementation details about multiple threading libraries
from the synopses of pthread*(3) manpages.

Reviewed by: deischen, davidxu

Remove mentions of libc_r.

Use 'manual page' instead of 'man page' for consistency.

Approved by: re (hrs)

Mechanically kill hard sentence breaks and double whitespaces.

Document interfaces that are supported by libthr.

Have a single set of POSIX threads man pages. The LIBRARY section
of each manpage lists libraries that have corresponding interfaces
implemented.

Prodded by: threads
Reviewed by: deischen

The .Fn function

mdoc(7) police: Use the new .In macro for #include statements.

Use ``.St -p1003.1-96''.

Introduce .Lb macro to libc_r manpages.

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.

Fix typos

PR: docs/14858
Submitted by: OKAZAKI Tetsurou <okazaki@be.to>

add pthread_cancel, obtained from OpenBSD.

eischen (Daniel Eischen) added wrappers to protect against cancled
threads orphaning internal resources.

the cancelability code is still a bit fuzzy but works for test
programs of my own, OpenBSD's and some examples from ORA's books.

add readdir_r to both libc and libc_r

add some 'const' attributes to function parameters

Reviewed by: eischen, jasone