downgrade required version of msgpack-python

For Ubuntu 14.04, downgrade the required version of msgpack-python.

Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
contrib: import tinyrpc library

https://pypi.python.org/pypi/tinyrpc/0.5
https://github.com/mbr/tinyrpc

Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
ryu.lib.hub: add logging wrapper for wsgi server

This patch adds a wrapper to relay the log of the wsgi server to the logger.

Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
bgp: use TCP_NODELAY for bgp connection

Disables Nagle to send data immediately.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
bgp: use sendall with lock

With the current design, multiple greenlets calls sendall() on a
single tcp socket. This leads to a corrupted bgp message.

This patch introduces mutex to work around the problem. However, I
hope that we _fix_ the design where only one greenlet call sendall()
on a signel tcp socket in the future.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
bgp: catch socket error with sendall

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>