title: Is it available to change the webviewer button icon of 'annotationStyleEditButton' & ' annotationDeleteButton'
body: <p>I want to change the icon of 'annotationStyleEditButton' and 'annotationDeleteButton' to a self designed PNG, I would like to know is those buttons are available to change the icon?</p>
  
  <p>I just found a method to change the Tools icon by using updateTool(), but seems we cannot change the 'style' and 'delete' button?</p>