Add 'python-backports-shutil-get-terminal-size'[1] package to
buildroot. Needed by IPython when building against Python2.
[1] https://pypi.python.org/pypi/backports.shutil_get_terminal_size
Reviewed-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
