python-pytrie: bump to version 0.3.1

For some reason (probably not on purpose) the license file was
removed from MANIFEST.in, and it's not available after package extraction.
I replaced it with PKG-INFO for now, and opened a PR on github:
https://github.com/gsakkis/pytrie/pull/3



Signed-off-by: Asaf Kahlon <asafka7@gmail.com>
Reviewed-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>