- 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

Create regression tests for ncal:

- A couple of tests to check if the layout of the generated calenders
is correct.

- A couple of tests to see if impossible combinations for -3, -A,
-m, -y etc properly abort.

- A couple of test to confirm that the order of -A, -B, -3 etc give
the right number of months.