updating quick start

doc/quick-start.md

 
 <img src="https://github.com/memspace/zefyr/raw/gitbook/assets/quick-start-rec-01.gif" width="600">
 
-### 04. Save document to a JSON file
+### 04. Save document to JSON file
 
 At this point we can already edit the document and apply styles, however if
 we navigate back from this page our changes will be lost. Let's fix this and
 
 <img src="https://github.com/memspace/zefyr/raw/gitbook/assets/quick-start-rec-02.gif" width="600">
 
-### 05. Load document from a JSON file
+### 05. Load document from JSON file
 
 Since we now have this document saved to a file, let's update our
 `_loadDocument` method to load saved file if it exists.