A few improvements to the slice docs. * Simplify `Option::iter_mut` doc example. * Document 'empty' corner-cases for `slice::{starts_with, ends_with}`. * Indicate 'true' as code-like.
A few improvements to the slice docs. * Simplify `Option::iter_mut` doc example. * Document 'empty' corner-cases for `slice::{starts_with, ends_with}`. * Indicate 'true' as code-like.