Array of Input / Mutation

Hello,

I got a question. I tried since hours to achieve to following:

Let's assume, we got an Object called User.

```
input User {
id int
name string
}
```

What I want to get is the possibility. to bind "User" to an array like [User] as an input and also have User available as Object,
Comming from node.js that was possible.
But how this will work with your lib? Is this even possible? I Can only add 1 Input-Type of this name, resolving either as list or as object, but not both, because the name "UserInput" was already registered.

Like this:
(This is just how I would do it in node.js)
```
mutation saveUser has inputObject of type User returning Bool
saveUser(input: User): Boolean
and mutation saveUsers has inputObject of type []User returning Bool
saveUsers(input: [User]): Boolean
```
Some go-code:
```
var UserIdInput = graphql.NewInputObject(graphql.InputObjectConfig{
Name: "UserInput",
Fields: graphql.InputObjectConfigFieldMap{
"id": &graphql.InputObjectFieldConfig{
Type: graphql.NewNonNull(graphql.Int),
},
"name": &graphql.InputObjectFieldConfig{
Type: graphql.NewNonNull(graphql.String),
},
},
})

var USERINPUT = map[string]graphql.Input{
"UserInput": UserInput,
// I know I can do: graphql.newList(UserInput), but I want both be possible for that inputtype
}
```