v0.20.2 Fix bug in parsing of IPv6 fragmentation header (offset & more_fragments)

Fixes the incorrect parsing of the fragment offset & more fragment fields in the IPv6 fragment header.

Thanks to @deusmatrix for finding the bug and providing a fix.

What's Changed

• release-0-20: Parse & encode the IPv6 fragment header in network byte order by @deusmatrix in #151 (cherry pick of #149 )
• release-0-20: Increment version to 0.20.2 by @JulianSchmid in #152

Full Changelog: v0.20.1...v0.20.2