RFC 2047 Encoder

Offers an encoder for RFC 2047 encoded words.

use rfc2047::rfc2047_encode;

#[test]
fn test_encode_rfc2047() {
    assert_eq!(
        "Foo  =?utf-8?q?a=C3=A4b?= =?utf-8?q?_=C3=A4?=  bar",
        rfc2047_encode("Foo  aäb ä  bar"),
    );
}

Words are encoded or not encoded as a whole. Only quoted-printable encoding is used.