Weak documentation of Spoofax contribution

[rlaemmel]

cc @MarcelH91 (as we discovered this in the lecture)
cc @sschauss (as Johannes may want to get help from Simon)

• There is a 404
• Neither the README nor the model hint at how to "play" with / "explore" the implementation -- both should, but the model really must (the README could be super-brief of sending one into right direction of needing to play with the IDE). In the model, it must be clear how to use the editor, the analysis, compilation. Different views are needed here including "Test", "Data", and "Capture" perspectives.
• More specifically, the generated code is missing in the view.

[le-cram]

It is not clear, whether Java classes exist for Transition / State / FSM.