feat: retrieve struct validation

[TommoLeedsy]

This PR adds support for struct validation, It pulls the information for the Go Validator V10 tags and converts into OpenAPI schemas.

For reference, natively gin uses the binding tag name as opposed to validate (which is the go validator default)

[Will-Mann-16]

Couple things to change that I can see - especially about expected behaviours

[Will-Mann-16]

Can we also add some form of documentation showcasing this behaviour?

[TommoLeedsy]

I did add a new example what else do you want me to add to showcase the feature?

[Will-Mann-16]

I did add a new example what else do you want me to add to showcase the feature?

On the readme or a new file in the docs showcasing this feature, this seems like one of our major selling points (maybe add to the bullet points at the top of the readme?)

[Will-Mann-16]

Think I'm not following this PRs purpose, is it just binding: required functionality or the whole validate suite? Is it all correctly passing to the schema?

[TommoLeedsy]

Its the whole validate suite thanks too validjsonator

[Will-Mann-16]

Also something I thought of, can we get an integration test demonstrating this behaviour

[TommoLeedsy]

I have now updated the README to include this feature. I will also add some integration test.

[TommoLeedsy]

I will merge main when #73 is merged in.

[TommoLeedsy]

@Will-Mann-16 I think this is now ready for a re-review!

[TommoLeedsy]

@Will-Mann-16 main has now been merged and all of the tests are passing. Ideally LS6-Events/validjsonator#4 would get merged in before this went in but its not a massive issue if it doesn't.