Add App Categries embed to docs

README.md

@@ -302,6 +302,7 @@ The function takes a command table of this format as a parameter:
 `appbox [NUM]` - my apps (number of lines);
 `applist [NUM]` - apps list (number of lines);
 `appfolders [NUM]` - app folders;
+`appcategories [NUM]` - app categries;
 `timer` - timers;
 `mailbox [NUM]` - mail widget;
 `dialer` - dialer;

samples/build_ui_sample.lua

@@ -15,5 +15,11 @@ function on_resume()
         "space 2",
         "text Timezones",
         "worldclock new_york kiev bangkok",
+        "space 2",
+        "text Categories",
+        "appcategories 3",
+        "space 2",
+        "text Apps",
+        "apps 2",
     }
 end