Add 'pathlib2'[1] package to Buildroot. Needed by 'pickleshare'
package, which is added in the next patch.
[1] https://pypi.python.org/pypi/pathlib2
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>
