New port: x11/wmsystemtray

wmsystemtray is a system tray dockapp using freedesktop.org system
tray protocol. It is designed to work with WindowMaker or another
WM, that supports dock applications (FVWM, AfterStep).

WWW: https://wmsystemtray.sourceforge.io

PR: 229033
Submitted by: ILUXA <iluxa@ex.ua>