Merge pull request #361 from Grahack/patch-3

Fix typo in comments of simple/core.cljs

examples/simple/src/simple/core.cljs

@@ -13,7 +13,7 @@
     (rf/dispatch [:timer now])))  ;; <-- dispatch used
 
 ;; Call the dispatching function every second.
-;; `defonce` is like `def` but it ensures only instance is ever
+;; `defonce` is like `def` but it ensures only one instance is ever
 ;; created in the face of figwheel hot-reloading of this file.
 (defonce do-timer (js/setInterval dispatch-timer-event 1000))