Fix: buffer is not killed when timeout
Parse response header even when timeout
Fix request-abort for the case buffer is killed already
Set status-code in request-response--timeout-callback
Add test request-get-parse-header-when-400
Merge branch 'handle-header-when-timeout'

EIN_ requires header info even when timeout, to workaround
a bug in url.el.  This patch enables to fetch status code
and header field even when request is shut down by an error
such as timeout.

.. _EIN: https://github.com/tkf/emacs-ipython-notebook
Bump to 0.2.0alpha1