Lifetime bounds are missing from the documentation

[tomjakubowski]

A question I see asked frequently is what the heck 'a: 'b means in a bound like this:

struct Foo<'a, 'b> where 'a: 'b {
    /* ... */
}

I didn't see this question addressed in either the section on bounds or the section on lifetimes.

[mdinger]

This is now explained in either lifetime/bounds or lifetime/coercion though 'a: 'b isn't listed under one of the rules...maybe it should be added.

Either way though, it's at least mostly covered

[steveklabnik]

Yup. Closing!