It seems that specifying NULL to bufferevent_set_timeouts() does not
remove timeout, which is described in bufferevent book (but it is not
described in header). As a workaround, we specify long enough timeout
to emulate removing timeout.

Chrome SPDY/3 flow control does not work well in spdy proxy
connection.

Log error string in case of network error

For upstream timeout, it seems OpenSSL backed bufferevent does not
remove timeout. Set large timeout as a workaround.

Jetty refuses connection if SSLv23_client_method is used.

This is just a sanity check in caes of path contains absoluteURI.

This option append X-Forwarded-For header field to the downstream
request.

To enable SPDY proxy, use --spdy-proxy option.  At time of this
writing, the only browser which supports SSL/SPDY proxy is Chrome.

Removed Location and Host header field rewrite.

CONNECT method supported. Fixed _str8cmp and _str9cmp comparison.
Support no content-length case.  Fixed hook_uri_run args. Run
hook_on_hdrs_complete if no header field is present. Supported empty
header value. Case insensitive match for particular header values
(e.g., keep-alive).

Signed-off-by: Piotr Sikora <piotr.sikora@frickle.com>