message: Document a type + add TODO
diff: @@ -8,6 +8,8 @@ use wasmer_vm::{init_traps, StoreId, TrapHandler, TrapHandlerFn};
  use wasmer_vm::StoreObjects;
  +/// Call handler for a store.
  +// TODO: better documentation!
  pub type OnCalledHandler = Box<
  dyn FnOnce(StoreMut<'_>) -> Result<OnCalledAction, Box<dyn std::error::Error + Send + Sync>>,
  >;
  