Func File

Some basic function primitives should live in a separate function library:

```
const id = x => x;
const compose = g => f => x => g(f(x));
const curry = bin => x => y => bin(x, y);
const uncurry = f => (x, y) => f(x)(y);
...
```

I'm not sure how much I'd use compose, but I feel like I can find several uses for curry.