project_spec.md

Introductory spec: https://docs.google.com/document/d/1Oz1VP4AC8YyEWFI_oHCe3GkRUIN1sRLcM5gfs1Z6knc/edit?usp=sharing

Detailed spec (RealityCards.sol): https://docs.google.com/document/d/1r7gaSrs6vHShrW3vOzEEULJSXM06OtS-kkheyhSDGGw/edit?usp=sharing