Improve lazy_static -> SharedBytes conversion

Created by: alexheretic

• Add From<&AsRef<[u8]>> for SharedBytes improving lazy_static case ergonomics. Allows:

  lazy_static! {
      static ref BYTES: Vec<u8> = vec![0, 1, 2, 3];
  }
  let shared_bytes: SharedBytes<'static> = (&*BYTES).into();

• Add SharedBytes conversion doc tests.
• Improve image example adding dynamic sizing to more easily switch fonts.
• Remove old confs from rustfmt.toml
• Run rustfmt