- 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

Start manpage with Dd macro and also remove a trailing whitespace
while here.

Add a new man page containing details of new locale-specific functions for
wctype.h, iswalnum_l(3). Add it and its functions to the Makefile.

Reviewed by: gavin, jilles
Approved by: theraven
MFC after: 5 days