x11/stalonetray: Update to 1.0.1

Switch to meson build system and use pkgconfig.
Add Xinerama support.
Use compiler.
Redefine ETCDIR to PREFIX/etc (without PORTNAME).
The meson.build patch disables stalonetray.sample renaming.

Changelogs:
https://github.com/d3adb5/stalonetray/releases/tag/1.0.1
https://github.com/d3adb5/stalonetray/releases/tag/1.0.0