New port: x11-wm/hikari: Stacking window manager with tiling capabilities

Hikari is a stacking window manager with additional tiling capabilities,
it is heavily inspired by the Calm Window manager (cwm(1)). Its core
concepts are windows, groups, sheets and the workspace.

WWW: https://hub.darcs.net/raichoo/hikari

PR: 237970
Submitted by: Alexander Sieg <alex@xanderio.de>
Differential Revision: https://reviews.freebsd.org/D20306