Character \r causes lex_string_invalid_json_char error

[kostyantyn]

Having \r character as a value breaks unmarshaling, however this symbol doesn't cause any issue using native Go implementation.

[yixizhang]

I can't reproduce the issue locally.

package main

import (
    "fmt"
    "github.com/pquerna/ffjson/ffjson"
)

type Response struct {
    PackageNumber string
}

func main() {
    blob, _ := ffjson.Marshal(&Response{
        PackageNumber: `\r`,
    })
    var resp Response
    ffjson.Unmarshal(blob, &resp)
    fmt.Println(resp)
}

This works great by printing out {\r}