Update api.md

docs/api.md

@@ -58,6 +58,12 @@ The messageData object will be converted to JSON and passed as a parsed object t
 ## Frontend
 
 ### events
+* `worksheetOpened`
+    * Called when a worksheet has been opened (probably from a file)
+    * Event data:
+        * `content` - the brief contents of the file, **can be modified**, but please don't
+* `worksheetReset``
+    * Called when a new worksheet has been initialized
 * `formulaRender`
     * Called before a LaTeX formula is sent to the renderer
     * Event data:
@@ -65,7 +71,9 @@ The messageData object will be converted to JSON and passed as a parsed object t
 * `pageSave`
     * Called before saving the contents of a page 
     * Event data:
+        * `pageId` - the id of the page
         * `content` - the HTML content, **can be modified**
+        * `data` - page metadata object, **can be modified**
 * `pageLoad`
     * Called before loading a page 
     * Event data 
@@ -74,4 +82,8 @@ The messageData object will be converted to JSON and passed as a parsed object t
     * Called when a page has been loaded and is about to be shown
     * Event data
         * `content` - the HTML content, **can be modified**
+* `pageAdd`
+    * Called when a page is about to be created 
+    * Event data:
+        * `pageName` - the name of the new page, **can be modified**