Completed sender removal.

src/field.rs

@@ -6,16 +6,6 @@ use uuid::Uuid;
 pub enum Field {
     Static(String),
     Uuid(Uuid),
-    Tx(Sender<Message>),
-}
-
-impl Field {
-    pub fn to_sender(&self) -> Result<Sender<Message>, String> {
-        match self {
-            Field::Tx(sender) => Ok(sender.clone()),
-            _ => Err("not a sender field".to_string()),
-        }
-    }
 }
 
 impl From<String> for Field {
@@ -49,7 +39,6 @@ impl fmt::Display for Field {
         match self {
             Field::Uuid(data) => write!(f, "{}", data),
             Field::Static(data) => write!(f, "{}", data),
-            Field::Tx(_) => write!(f, "{}", "message sender"),
         }
     }
 }