Vinci Xu

Hi, deankarn, some code of the go-download is invalid(because its dependency is updated), may we should update go-download to use go mod.

It seems like the library do not support [Token Revocation](https://tools.ietf.org/html/rfc7009),here any plan for it?

Now droplet have already support two codec: - json - multipart form data(using to read file) We need to a implement codec for `application/x-www-form-urlencoded`

Now droplet already support: - gin - go-restful We can implement more.