New port: finance/py-python-bitcoinlib: Swiss Army Knife of the Bitcoin protocol

[kai]

Summary

Provides an easy interface to the bitcoin data structures and protocol. The
approach is low-level and "ground up", with a focus on providing tools to
manipulate the internals of how Bitcoin works.

WWW: https://github.com/petertodd/python-bitcoinlib/

Test Plan

• poudriere (11.2-, 12.0-RELEASE, 13.0-CURRENT@r344874 amd64 + i386) for each py27 + py36 flavor -> OK
• portlint -> OK
• Runtime tests -> OK