- 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

Set proper permissions on the generated osreldate.h file; a file readable
only by root can cause install problems, especially over nfs.

Submitted by: jilles@
Approved by: re (gjb)

Prevent the set -e from mk-osreldate.sh from propagating into newvers.sh.
This would cause detection of old versions of SVN to cause fatal errors
instead of being caught and handled, which would make the build fail if
the tree had been checked out with an older version of SVN (e.g. 1.6).

Discussed with: gjb
Approved by: re (marius)

Create a separate script to generate osreldate.h rather than sourcing
newvers.sh into a temporary subshell with inline make rules.

Using a separate script fixes a variety of problems, including establishing
the correct dependencies in the makefiles. It also eliminates a problem
with the way newvers.sh uses `realpath $0`, because $0 expands differently
within a script sourced into a rule in a makefile depending on the version
of make and of /bin/sh being used. The latter can cause build breakage in a
cross-build environment, and can also make it difficult to compile 10.0 on
older pre-10.0 systems.

PR: 160646 174422
Submitted by: Garrett Cooper <yaneurabeya@gmail.com>
Approved by: re (gjb)
MFC after: 2 weeks