Added rust code

src/managers/user_manager.rs

@@ -0,0 +1,21 @@
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Deserialize, Serialize)]
+struct UserManager {
+    user: models::User,
+    ica_action: models::IcarusAction,
+}
+
+impl UserManager {
+    // TODO: Implement
+    pub fn retrieve_user(&self) -> models::User {
+        return models::User {
+            username: String::from(""),
+            password: String::from(""),
+        };
+    }
+
+    // TODO: Implement
+    fn parse_user_from_actions(&self) {
+    }
+}