API Update API to reflect changes in silverstripe/cms

Author: GuySartorelli

src/Model/Blog.php

@@ -142,7 +142,7 @@ class Blog extends Page implements PermissionProvider
 
     private static $class_description = 'Adds a blog to your website.';
 
-    private static $icon_class = 'font-icon-p-posts';
+    private static $cms_icon_class = 'font-icon-p-posts';
 
     /**
      * {@inheritdoc}

src/Model/BlogPost.php

@@ -54,7 +54,7 @@ class BlogPost extends Page
     /**
      * @var string
      */
-    private static $icon_class = 'font-icon-p-post';
+    private static $cms_icon_class = 'font-icon-p-post';
 
     /**
      * @var array