Correct links to lib.rs

[reynn]

Currently the links to lib.rs do not link to the crate itself but instead either link to keywords or nothing at all. This adds the necessary /crates/

Examples:

• Current link to once_cell crate https://lib.rs/once_cell. This goes to a page not found
  • Correct link to once_cell crate https://lib.rs/crates/once_cell
• Current link to time crate https://lib.rs/time. This redirects to the time keywords page instead of the crate.
  • Correct link to time crate https://lib.rs/crates/time

[nicoburns]

Thanks! Don't know how I missed this!