docs fixes (#362)

* minor grammar fixes in docs

* Docs: add comma after however

docs/en/actions.md

@@ -2,7 +2,7 @@
 
 Actions are similar to mutations, the difference being that:
 
-- Instead of mutating the state, actions commits mutations.
+- Instead of mutating the state, actions commit mutations.
 - Actions can contain arbitrary asynchronous operations.
 
 Let's register a simple action:
@@ -77,7 +77,7 @@ A more practical example of real-world actions would be an action to checkout a
 ``` js
 actions: {
   checkout ({ commit, state }, payload) {
-    // save the current in cart items
+    // save the items currently in the cart
     const savedCartItems = [...state.cart.added]
     // send out checkout request, and optimistically
     // clear the cart

docs/en/modules.md

@@ -1,6 +1,6 @@
 # Modules
 
-Due to using a single state tree, all state of our application is contained inside one big object. However as our application grows in scale, the store can get really bloated.
+Due to using a single state tree, all state of our application is contained inside one big object. However, as our application grows in scale, the store can get really bloated.
 
 To help with that, Vuex allows us to divide our store into **modules**. Each module can contain its own state, mutations, actions, getters, and even nested modules - it's fractal all the way down: