Payouts code (#765)

* push to rebase

* finish most

* finish most

* Finish impl

* Finish paypal

* run prep

* Fix comp err

src/models/error.rs

@@ -0,0 +1,8 @@
+use serde::{Deserialize, Serialize};
+
+/// An error returned by the API
+#[derive(Serialize, Deserialize)]
+pub struct ApiError<'a> {
+    pub error: &'a str,
+    pub description: &'a str,
+}