Initial version of libgames-scores

Fake pull request for initial review of libgames-scores.

Hint: scroll down towards the bottom to get to the newer comments.
When we define lambdas, we put the opening brace on the initial line, right after the =>.  They're a lot easier to read this way; with the brace on a new line, away from the =>, it looks too much like a function definition.

This actually does make sense!