[ANN] kgio 2.11.0 - legacy I/O for legacy Ruby + Unix

kgio provides non-blocking I/O methods for Ruby without raising
exceptions on EAGAIN and EINPROGRESS. It is intended for use with the
unicorn Rack server, but may be used by other applications (that run on
Unix-like platforms).

Note: I do not recommend using kgio for future applications, Ruby 2.x
has a lot of the functionality of kgio and Ruby 2.3 has even more.
Keep an eye on the NEWS file for Ruby 2.3+ releases.
However, I'll continue maintaining kgio for legacy purposes
indefinitely.

* homepage: https://bogomips.org/kgio/
* public mailing list: kgio-public@bogomips.org
* git clone git://bogomips.org/kgio.git
* Atom feed https://bogomips.org/kgio/NEWS.atom.xml
* mailing list archives: https://bogomips.org/kgio-public/

Changes: kgio 2.11.0 - reverting 2.10.0 breakage

    Mainly this release reverts back to kgio 2.9.3 behavior by
    supporting "autopush" functionality in the C extension.
    Removing this feature in 2.10.0 was a monumental mistake(*) on
    my part which caused a performance regression for ONE known user
    of kgio on the deprecated (but supported) Rainbows! server.

    This release does not affect known users outside of Rainbows!,
    but we may have unknown users, too.

    The attempt at a pure Ruby version of autopush had flaws and
    regressions in real-world testing, so that was abandoned.

    So yeah, kgio will be supported indefinitely even in the face
    of internal changes to MRI, but I strongly discourage its use
    for new projects.
    Users who only support Ruby 2.3 (and later) are encouraged to
    use `exception: false` with all *_nonblock methods.

    4 changes since 2.10.0:

          resurrect Kgio.autopush support in pure Ruby [REVERTED]
          reinstate the original (and dangerous) autopush in C
          TODO: update with Ruby 2.3 status
          test: increase test data sizes to fill socket buffers

    (*) - as was making this a separate project, at all