ET++ class library restored to working order

[Nemanja Simonovic <redporter%dev63.com@localhost>]

Hello,

here is repo with ET++ 2.2 modernised for modern C++ and ported to
NetBSD and Linux. Code is early 90's vintage so it should be usable
on older machines and monochrome monitors. I think (didn't try) it
should be buildable with base system only, without pkgsrc.

https://github.com/redporter/ETPlusPlus