Log Message:
Update ruby-kgio to 2.8.1.

=== kgio 2.8.1 - minor improvements and test fixes / 2013-09-11 00:22 UTC

  Improved error reporting for kgio_accept/kgio_tryaccept.
  Minor size reduction throughout.  There are also several
  test case fixes for race conditions.

  Thanks to Hleb Valoshka and the Debian project for all the
  help with this release!

  Eric Wong (7):
        check syscall returns against < 0 instead of == -1
        accept: more informative exception on unknown family
        test_tryopen: skip EACCES test when euid == 0
        test/lib_read_write: account for larger-than-normal pipes
        test_poll: avoid potentially thread-unsafe test
        test_poll: preserve original trap(:USR1) handler
        test_poll: be less dependent on signal handler ordering

  Hleb Valoshka (4):
        Change prefix of temporary sockets to prevent races
        Don't dump 20M in case of failure
        Create own directory for every unix socket in unit tests
        Close tempfile and unlink it immediately.

=== kgio 2.8.0 - TCP Fast Open, writev/trywritev / 2013-01-18 10:52 UTC

  TCP Fast Open in Linux 3.7 and later is now supported
  in the client via Kgio::Socket#kgio_fastopen.

  This release also adds the kgio_writev and
  kgio_trywritev methods, thanks to funny-falcon