- 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

sync the code with the version in head. which the exception of
svn 275358 (M_FLOWID deprecation, only a couple of lines)
which cannot be merged.

if_lem_netmap.h, if_re_netmap.h:
- use the same (commented out) function to update the stat counters
as in HEAD. This is a no-op here

netmap.c
- merge 274459 (support for private knote lock)
and minor changes on nm_config and comments

netmap_freebsd.c
- merge 274459 (support for private knote lock)
- merge 274354 (initialize color if passed as argument)

netmap_generic.c
- fix a comment

netmap_kern.h
- revise the lock macros, using sx locks;
merge 274459 (private knote lock)

netmap_monitor.c
- use full memory barriers

netmap_pipe.c
- use full memory barriers, use length from the correct queue
(mostly cosmetic, since the queues typically have the same size)

MFC 270063: update of netmap code
(vtnet and cxgbe not merged yet because we need some other mfc first)

MFC 267328:
change the netmap mbuf destructor so the same code works also on FreeBSD 9.
For head and 10 this change has no effect, but on stable/9 it would cause
panics when using emulated netmap on top of a standard device driver.

MFC after: 3 days

sync netmap code with the version in HEAD:
- fix handling of tx mbufs in emulated netmap mode;
- introduce mbq_lock() and mbq_unlock()
- rate limit some error messages
- many whitespace and comment fixes

missing files from previous commit...