Document that 0.4.14 is yanked

[quodlibetor]

Got to improve some tests

[quodlibetor]

error[E0412]: cannot find type `Vec` in this scope
   --> /home/runner/.cargo/registry/src/github.com-1ecc6299db9ec823/chrono-0.4.14/src/format/mod.rs:452:26
    |
452 |     let am_pm_lowercase: Vec<_> = am_pm.iter().map(|x| x.to_lowercase()).collect();
    |                          ^^^ not found in this scope
    |
help: consider importing one of these items
    |
21  | use alloc::prelude::v1::Vec;
    |
21  | use alloc::vec::Vec;