Right now, we ensure all Windows users have 'wget', 'tar', and the like installed.
For some of the missions, we like to recommend in the "high"ly helpful hints
that people use 'wget' to download files distributed as part of the mission.
That will fail on default Fedora systems, for example, because those systems do
not ship 'wget' by default.
Therefore we should:
* In each hint that mentions running a command, indicate that if you see
"command not found" that you should go to some page with instructions for what
* Write that page.