[WIP] Fake games for real reasons

[abachman]

vibed a bit on the last evening of ruby for good and made a fake game demonstrating the GameAttempt API from #117

usage

In development, after running bin/rails db:seed and starting the server with bin/dev:

• visit: http://localhost:3000/classroom_rosters/j3B8BEMxYm7iK_QY5rXLN6pObd5nBt1j1WTFb3bdYO0
• select a student name
• visit: http://localhost:3000/games/1/play