add mail for requesting fee

src/model/user.rs

@@ -25,7 +25,7 @@ const REGULAR: i32 = 22000;
 const UNTERSTUETZEND: i32 = 2500;
 const FOERDERND: i32 = 8500;
 
-#[derive(FromRow, Debug, Serialize, Deserialize)]
+#[derive(FromRow, Debug, Serialize, Deserialize, Clone)]
 pub struct User {
     pub id: i64,
     pub name: String,
@@ -106,6 +106,7 @@ pub struct Fee {
     pub name: String,
     pub user_ids: String,
     pub paid: bool,
+    pub users: Vec<User>,
 }
 
 impl Default for Fee {
@@ -121,6 +122,7 @@ impl Fee {
             name: "".into(),
             parts: Vec::new(),
             user_ids: "".into(),
+            users: Vec::new(),
             paid: false,
         }
     }
@@ -139,6 +141,7 @@ impl Fee {
         self.name.push_str(&user.name);
 
         self.user_ids.push_str(&format!("user_ids[]={}", user.id));
+        self.users.push(user.clone());
     }
 
     pub fn paid(&mut self) {