- 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 section .note.GNU-stack for assembly files used by 386 and amd64.

Use, in uncovered part, the END() macro in order to improve debugging.
In this specific case, Valgrind won't get confused when analyzing such
functions.

Sponsored by: Sandvine Incorporated
Tested by: emaste
MFC: 3 days

Implement and document remquo() and remquof().