Add docs for History

src/utils/history.rs

@@ -12,6 +12,8 @@ pub enum History {
     RemovedFromRight = "RemovedFromRight",
 }
 
+/// Simple enum for describing the result of `reconcile` in a flat list.
+/// When compiled to WASM, the enum values are the same as their names.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 #[cfg(not(feature = "wasm"))]
 pub enum History {