Gipc

-----------------------------
- Don't provide and use distribute_setup.py anymore. Thanks to Guy
Rozendorn.

- Slightly improve pipe write performance (measured improvement of up to
10 % in data throughput as well as message transmission rate).

----------------------------
- Fix `issue 1 <https://github.com/jgehrcke/gipc/issues/1>`_: don't
import gipc from setup.py anymore.

- Fix: make GProcess' exitcode return ``None`` if ``Popen`` object still
not existing.

- Fix ``GProcess.is_alive``: Raise exception if process has not been
started yet.

- Create event object after forking instead of before (one reference to old
Hub object less in child).

- Make test classes newstyle. Doh.

- Modify documentation theme.

----------------------------
- Add bidirectional message transfer channels for IPC.

- Prevent multiprocessing from swallowing SIGCHLD signals. Eliminates race
condition between poll via os.waitpid() and libev child watchers.

- Don't pass dispensable gipc handles to child.

- Properly deal with handles that are locked for I/O operation while being
inherited by child.

- Various minor code changes, and a new class of unit tests for more complex
scenarios.

----------------------------
- Remove gevent hub threadpool before destroying hub in child (makes gevent
reset in child work more reliable).

----------------------------
- Initial release.