Attempt to follow the instructions at https://github.com/AArnott/CodeGeneration.Roslyn

I eventually got things working.

See AArnott/CodeGeneration.Roslyn#46 for a discussion of what I had to do on top of the walkthrough instructions (or rather, reordering the walkthrough instructions) to get it to work.

• https://github.com/lionfire/class-state-machine - Define your states and transitions in enums, and your Can/On/Leaving/etc. methods will automatically be called by convention.