Log Message:
Update atf to 0.12:

* Added the ATF_REQUIRE_THROW_RE to atf-c++, which is the same as
  ATF_REQUIRE_THROW but allows checking for the validity of the exception's
  error message by means of a regular expression.

* Added the ATF_REQUIRE_MATCH to atf-c++, which allows checking for a
  regular expression match in a string.

* Changed the default timeout for test cases from 5 minutes to 30 seconds.
  30 seconds is long enough for virtually all tests to complete, and 5
  minutes is a way too long pause in a test suite where a single test case
  stalls.

* Deprecated the use.fs property.  While this seemed like a good idea in
  the first place to impose more control on what test cases can do, it
  turns out to be bad.  First, use.fs=false prevents bogus test cases
  from dumping core so after-the-fact debugging is harder.  Second,
  supporting use.fs adds a lot of unnecessary complexity.  atf-run will
  now ignore any value provided to use.fs and will allow test cases to
  freely access the file system if they wish to.

* Added the atf_tc_get_config_var_as_{bool,long}{,_wd} functions to the atf-c
  library.  The 'text' module became private in 0.11 but was being used
  externally to simplify the parsing of configuration variables.

* Made atf-run recognize the 'unprivileged-user' configuration variable
  and automatically drop root privileges when a test case sets
  require.user=unprivileged.  Note that this is, by no means, done for
  security purposes; this is just for user convenience; tests should, in
  general, not be blindly run as root in the first place.