devel/lua-lunitx: Update to 0.8.2

Release 0.8.2 adds Lua 5.5 support.

Changelog: https://github.com/dcurrie/lunit/blob/0.8.2/CHANGES

While here, update my maintainer email.

Approved by: dch (mentor)
Pull Request: https://github.com/freebsd/freebsd-ports/pull/552