Log Message:
Updated atf to 0.21.

Add test target.

Changes in version 0.21
***********************

Released on October 23rd, 2014.

* Restored the atf(7) manual page to serve as a reference to all the other
  manual pages shipped by ATF.

* Added the -s flag to atf-sh to support specifying the shell interpreter
  to be used.

* Removed ATF_WORKDIR.  The only remaining consumers have been converted to
  use the standard TMPDIR environment variable.  As a benefit, and because
  Kyua forces the TMPDIR to live within the test case's work directory,
  any stale files left behind by ATF will be automatically cleaned up.

* Documented the environment variables recognized by each component in the
  relevant manual pages.  This information was lost with the atf-config(1)
  removal.

* Added a new "require.diskspace" metadata property to test cases so that
  they can specify the minimum amount of disk space required for the test
  to run.

* Renamed the atf-{c,c++,sh}-api(3) manual pages to atf-{c,c++,sh}(3) for
  discoverability purposes.  Symbolic links are provided for the time
  being to still make the old names visible.

* Issue #5: Recommend the (expected, actual) idiom for calls to the test
  macros in the manual pages.

* Issue #7: Stopped catching unhandled exceptions in atf-c++ tests.  This
  propagates the crash to the caller, which in turn allows it to obtain
  proper debugging information.  In particular, Kyua should now be able to
  extract a stacktrace pinpointing the problem.

* Issue #8: Fixed atf-c/macros_test:use test failures spotted by the clang
  that ships with FreeBSD 11.0-CURRENT.

* Issue #12: Improved documentation of atf-sh(3) and atf-check(1) by better
  explaining how they relate to each other.

* Issue #14: Stopped setting 'set -e' in atf-sh.  This setting was
  initially added as a way to enable a "strict" mode in the library and to
  make test cases fail fast when they run unprotected commands.  However,
  doing so in the library is surprising as the responsibility of enabling
  'set -e' should be on the user's code.  Also, 'set -e' introduces
  inconsistent behavior on subshells and users do not expect that.

* Issue #15: Fixed atf_utils_{fork,wait} to support nested calls.

* Issue #16: Fixed test failures (by removing a long-standing hack) on
  systems that lack \e support in printf(1).

* Issue #19: Removed stale references to atf-config and atf-run.