The on_ctrl_not_send_callback, on_ctrl_recv_parse_error_callback and
on_unknown_ctrl_recv_callback were added. The latter 2 callbacks are
purely debugging purpose. In on_ctrl_not_send_callback, If sending
SYN_REPLY failed, issue RST_STREAM to avoid a stream hanging around.
When deciding whether to close the client connection, check
request_connection_close_ of Downstream in addition of
response_connection_close_. Also we only add "Connection: Keep-Alive"
header to the HTTP/1.0 or HTTP/0.9 clients.
When --enable-src is given, the programs in src directory will be
built. If --disable-src is given, those programs will not be built. If
none of them are given, --enable-src is assumed.
To distinguish the to-be-installed programs and non-installable
example source code, the former programs, spdycat, spdydyd and shrpx,
were moved to src directory. spdynative was removed from Makefile
because it does not appeal to any users much.
