[Buildroot] Python backport packages

[Yegor Yefremov]

python-tornado 4x needs
https://pypi.python.org/pypi/backports.ssl_match_hostname
It looks like there is some kind of infrastructure for backport
packages: https://pypi.python.org/pypi/backports/1.0

aside from ssl_match_hostname, there is also
https://pypi.python.org/pypi/backports.lzma

Should I just add "ssl_match_hostname" as is or should I make extra
folder in package/Config.in, as we have for core and external
packages?

Yegor