Do not suggest to use the closed interval syntax

[leonardo-m]

I suggest to remove or disable this:
https://rust-lang-nursery.github.io/rust-clippy/master/index.html#range_plus_one

Because in some cases the ..= closed intervals are slower (less efficient) than regular intervals.

[oli-obk]

Do you have any sources about the slowdown?

[leonardo-m]

An example here:
rust-lang/rust#45222

[dalcde]

This issue still persists. It would be helpful to at least note this in the "Known problems" section.