ENH: update main page for pdfgui2

Author: dragonyanglong

index.rst

@@ -8,10 +8,10 @@
 .. raw:: html
 
    <strong>
-   DiffPy-CMI upgrade 3.0 for Python 2 and 3 is now available! (Mar 14, 2019)
+   Please update your PDFgui to PDFgui v2.0, the first Python 3 version of the software (May 10, 2023)
    </strong>
    &nbsp;
-   <a href="products/diffpycmi/index.html" class="btn btn-large btn-success btn-flat">Get DiffPy-CMI</a>
+   <a href="products/pdfgui.html" class="btn btn-large btn-success btn-flat">Get PDFgui v2.0</a>
    &nbsp;
    <a href="acknowledgements.html">Credits</a></p>