Move the Default implementation into more generate_attribute!.

src/data_forms.rs

@@ -25,13 +25,7 @@ generate_attribute!(FieldType, "type", {
     TextMulti => "text-multi",
     TextPrivate => "text-private",
     TextSingle => "text-single",
-});
+}, Default = TextSingle);
-
-impl Default for FieldType {
-    fn default() -> FieldType {
-        FieldType::TextSingle
-    }
-}
 
 #[derive(Debug, Clone)]
 pub struct Option_ {

src/jingle.rs

@@ -41,13 +41,7 @@ generate_attribute!(Senders, "senders", {
     Initiator => "initiator",
     None => "none",
     Responder => "responder",
-});
+}, Default = Both);
-
-impl Default for Senders {
-    fn default() -> Senders {
-        Senders::Both
-    }
-}
 
 #[derive(Debug, Clone)]
 pub struct Content {

src/message.rs

@@ -108,13 +108,7 @@ generate_attribute!(MessageType, "type", {
     Groupchat => "groupchat",
     Headline => "headline",
     Normal => "normal",
-});
+}, Default = Normal);
-
-impl Default for MessageType {
-    fn default() -> MessageType {
-        MessageType::Normal
-    }
-}
 
 type Lang = String;
 type Body = String;