add support for cduce, the 80th language

  - piet failed misteriously, so also added libgd-dev
Add support for Chef, the 81st language

  - Fix dependencies for piet
add support for D, the 82nd language
add the number of languages to the README

  - Since we pin the commit from mame's original  quine relay,
    we might as well document which version of the QR the vagrant
    file works for.
add mame's ouroboros graphic listing the languages, why not?
really add ouroboros image with list of languages, this time