This uses the github.com:googlei18n/region-flags and imagemagick to generate 27x27 flag pngs. The flags have a 1px #e0e0e0 border and transparent padding such that each flag is of the same height (17px including the border).
All of those cpx invocations were getting unwieldy, and I suspect the exotic
quoting needed to run them under parallelshell was breaking things on windows.
Replace the unwieldy cpx invocations with an unwieldy custom script.