- 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 regression tests for newsyslog. These are far from a complete
test of newsyslog, as they were mainly made to test 'newsyslog -t',
but they do test the basic functionality.

The test 'framework' was based on dds@'s code in
src/tools/regression/bin/mv/.

Note that currently these tests are not fully correct for the
non-timestamp based rotation case, as it seems like newsyslog actually
by default keeps a file too much around.

MFC after: 3 weeks