README with a short description of each tool

[jmzumg]

It would be nice if this repo had a README with a short description of each tool, It is rather difficult to search mircwiki.rsna.org and figure out is what is what.

[jmzumg]

I've just noticed that many of the installer show a short description of the application as a splash screen, this is useful but I still think it would be more useful in the README

[jmzumg]

Created a PR here #2