Return field name in errors

[mojixcoder]

As you might know, so many people are using this package for validating http requests.
Error handling is kinda tricky in this case. For example we have a field called first_name but in the error message we can't access this and we get FirstName(golang struct field name).
Can we add one more tag to get the name that we want instead of golang struct filed name?
Here is an example:

type User struct{
    FirstName string `validate:"fieldname=first_name,required"`
}

And in error handling:

for _, err := range err.(validator.ValidationErrors) {
    fmt.Println(err.FieldName())
}

It's not really nice to get first_name in the request and return FirstName in the response error msg.

I know it can be handled manually with a little bit extra work.
But can you please handle it in the package? because I think it's a common problem.