Make it easier to find out how to silence clippy

I often find I want to silence some clippy warning (for example, clippy has just warned me about assert!(!(d<d)), which is reasonable, except it's in a test and I really do want to check it).

While it might add more noise, I wonder if the 'help' line could be extended to say how to silence the warning, for example (I've added to the end)

warning: equal expressions as operands to `<`
   --> src/datastructures/digraph.rs:174:18
    |
174 |         assert!(!(d < d));
    |                  ^^^^^^^
    |
    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#eq_op ,
       or silence this warning by adding #[allow(clippy::eq_op)] to the function

Or, this information could be added to https://rust-lang.github.io/rust-clippy/master/index.html#eq_op .

At the moment, (because I have a bad memory and don't do it often), every time I want to silence a clippy warning I have to google for it.

Start by examining how Clippy warning help text is generated and how the lint documentation at https://rust-lang.github.io/clippy/master/index.html#eq_op is connected to each warning. Compare the proposed inline #[allow(clippy::eq_op)] guidance with linking only to the documentation, and define done as making the silencing method discoverable in the warning or documented page.