iq: Implement the Iq*Payload traits on every possible payload.

src/bind.rs

@@ -12,6 +12,7 @@ use minidom::Element;
 use error::Error;
 use jid::Jid;
 use ns;
+use iq::{IqSetPayload, IqResultPayload};
 
 #[derive(Debug, Clone, PartialEq)]
 pub enum Bind {
@@ -29,6 +30,9 @@ impl Bind {
     }
 }
 
+impl IqSetPayload for Bind {}
+impl IqResultPayload for Bind {}
+
 impl TryFrom<Element> for Bind {
     type Err = Error;