Function normalize 

pub fn normalize(s: &str) -> String

Trim, lowercase, and strip diacritics.

Steps:

1. Trim surrounding whitespace
2. Lowercase (Unicode-aware)
3. Decompose to NFD
4. Drop combining marks (Unicode category Mn)
5. Recompose to NFC

Examples

use matchr::normalize;

assert_eq!(normalize("Café"), "cafe");
assert_eq!(normalize(" Hello "), "hello");