Update 03 notebook description in README.

Author: jeffcarlin

README.md

@@ -11,7 +11,7 @@ These notebooks have drawn from these repositories:
 |---|---|
 | 01. Intro to DP0 Notebooks | Use a python notebook; query a DC2 catalog and plot data; retrieve and display a DC2 image. |
 | 02. Intro to TAP | Discover, query, and retrieve DC2 catalog data with the Table Access Protocol (TAP) service. |
-| 03. Intro to AFW Display | Display, manipulate, and overlay data onto DC2 images. |
+| 03. Image Display and Manipulation | Display and manipulate DC2 images, explore image mask planes, create cutout and RGB images. |
 | 04. Intro to Butler | Discover, query, retrieve, and display DC2 images and catalog data with the Generation 3 Butler. |
 | 05. Intro to Source Detection | Learn to use the LSST Science Pipelines tasks for image characterization, source detection, deblending, and measurement. Learn to interact with a source footprint. |