- 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

More changes to use __FBSDID() for setting rcsids. For the filter
programs, minor Makefile changes are needed to find lp.cdefs.h.
For lpf.c, the 'sccsid' line is formatted to match style(9), and
a 'From:' is removed so the sccsid returns to what it was back
in the days of '-r CSRG' (1994).

Reviewed by: discussed with bde and obrien
MFC after: 15 days

Include stdlib.h for atoi declaration
Add $FreeBSD$ while I'm here.

Add Russian printer filters, mandatory because hardware code page 866
is different with KOI8-R