Replace reflector configuration with Options struct and helper methods

[samlown]

The current Reflector struct should be replaced with a set of option functions provided at run time. This a more idiomatic approach and results in an immutable configuration for each reflection invocation.

The objective is to end up with something like this:

s := jsonschema.Reflect(TestUser{}, jsonschema.WithBaseSchemaID("https://example.com/schemas"))

Shared options can be assigned to an array:

opts = []jsonschema.Option{
  jsonschema.WithBaseSchemaID("https://example.com/schemas"),
  jsonschema.AllowAdditionalProperties(),
}
s := jsonschema.Reflect(TestUser{}, opts...)

[charbonnierg]

Hi @samlown

I saw this PR and decided to give it a try. I've got a branch with options as described in this issue: main...charbonnierg:jsonschema:main.

One thing that I changed compared to your example is that I renamed AllowAdditionalProperties into WithAdditionalPropertiesAllowed because I prefer having all options starting with With, it makes life easier when using an IDE IMO 😅.

Would you like me to open a pull request ?