Slight improvement to the 'no hydrated stores' error (#605)

* Slight improvement to the 'no hydrated stores' error
This should make it more clear that rendering
`redux_store_hydration_data` is required.
This should more cleanly differentiate the two cases
* Change hydrated stores error to be a list of actions

Author: cookiefission

node_package/src/StoreRegistry.js

@@ -39,10 +39,12 @@ export default {
     const storeKeys = Array.from(hydratedStores.keys()).join(', ');
 
     if (storeKeys.length === 0) {
-      const msg = 'There are no stores hydrated and you are requesting the store ' +
-        `${name}. This can happen if you are server rendering and you do not call ` +
-        "redux_store near the top of your controller action's view (not the layout) " +
-        'and before any call to react_component.';
+      const msg =
+`There are no stores hydrated and you are requesting the store ${name}.
+This can happen if you are server rendering and either:
+1. You do not call redux_store near the top of your controller action's view (not the layout)
+   and before any call to react_component.
+2. You do not render redux_store_hydration_data anywhere on your page.`;
       throw new Error(msg);
     }