Update README.md

README.md

@@ -159,6 +159,7 @@ easyMDE.value('New input for **EasyMDE**');
 - **promptTexts**: Customize the text used to prompt for URLs.
   - **image**: The text to use when prompting for an image's URL.  Defaults to `URL of the image:`.
   - **link**: The text to use when prompting for a link's URL. Defaults to `URL for the link:`.
+- **iconClassMap**: Used to specify the icon class names for the various toolbar buttons.
 - **uploadImage**: If set to `true`, enables the image upload functionality, which can be triggered by drag and drop, copy-paste and through the browse-file window (opened when the user click on the *upload-image* icon). Defaults to `false`.
 - **imageMaxSize**: Maximum image size in bytes, checked before upload (note: never trust client, always check the image size at server-side). Defaults to `1024 * 1024 * 2` (2 MB).
 - **imageAccept**: A comma-separated list of mime-types used to check image type before upload (note: never trust client, always check file types at server-side). Defaults to `image/png, image/jpeg`.