fix example

Author: ladyada

README.rst

@@ -34,10 +34,12 @@ For a board with a built-in display.
 
     import board
     import terminalio
-    from adafruit_display_text import text_area
+    from adafruit_display_text import label
 
     text = "Hello world"
-    text_area = text_area.TextArea(terminalio.FONT, text=text, width=len(text))
+    text_area = label.Label(terminalio.FONT, text=text)
+    text_area.x = 10
+    text_area.y = 10
     board.DISPLAY.show(text_area)