Tag oapi-codegen

 Note

For the last ~7 weeks on-and-off rewriting the documentation for oapi-codegen which has needed a fresh version for a bit of time. On top of that, I've spent pretty much the last two days solidly finishing it off, and am very glad to have just merged it!

Documentation can be difficult to do - especially if you're redoing it all in one go - but am hoping it's in a much better place for new and existing users alike!

Also introduces a CONTRIBUTING.md for the first time, and I ended up adding 14 new examples to the examples directory because I couldn't quite remember how things worked πŸ˜…