Colors are not reset properly

[bacongravy]

When running in a terminal configured with foreground color other than black, the current handing of colors is incorrect. The text color is set to black at the end of the script, even if that was not the original text color. On a black background, this makes the text invisible!

It looks like we need to use tput sgr0 to reset the color, instead of tput setaf 0, which sets it explicitly to black.