RealIP

获取客户端的真实IP，先判断请求头是否有X-Forwarded-For，如果没有再取X-Real-Ip，都没有则从连接IP中取。

Example

package main
import (
    "log"
    "github.com/vicanso/elton"
    "github.com/vicanso/elton/middleware"
)
func main() {
    e := elton.New()
    e.Use(middleware.NewDefaultResponder())
    e.GET("/", func(c *elton.Context) (err error) {
        log.Println(c.RealIP())
        c.Body = "Hello, World!"
        return
    })
    err := e.ListenAndServe(":3000")
    if err != nil {
        panic(err)
    }
}