Add README Badges

[nobodywasishere]

https://shields.io/

There could be a link on every doc page at the bottom Copy README Badge, or the format for specifying them could be consistent. I'm unsure if these should just be pure links, or be dynamic and return the latest docs version.

Something like this:

[nobodywasishere]

[devnote-dev]

This is the logo style I use for certain projects, even if this doesn't become the official for this project I'd still use this one for Crystal projects.