chore(pacman): add `stress` package
chore(pacman): add `stress` package

For CPU stress testing:

    https://wiki.archlinux.org/index.php/Stress_testing

eg. `stress -c 32` to hammer CPU.

wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent