add alt= tag to icon images to make the html validator happy.

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@50827 15284696-431f-4ddb-bdfa-cd5b030d7da7

gui/wxpython/docs/wxGUI.Modeler.html

@@ -27,7 +27,9 @@ The modeler currently allows to:
 </ul>
 
 <center>
-<br><img src="wxGUI_modeler.jpg" border="1"><br><br>
+<br>
+<img src="wxGUI_modeler.jpg" border="1" alt="screenshot">
+<br><br>
 </center>
 
 <h2>SEE ALSO</h2>

gui/wxpython/docs/wxGUI.Vector_Digitizer.html

@@ -47,7 +47,9 @@ vector map" button in the "Additional Tools" menu on the Digitzer Toolbar.
 <h3>DIGITIZER TOOLBAR</h3>
 
 <center>
-<br><img src="wxGUI_vector_digitizer_toolbar.jpg" border="1"><br><br>
+<br>
+<img src="wxGUI_vector_digitizer_toolbar.jpg" border="1" alt="toolbar">
+<br><br>
 </center>
 
 <dl>

gui/wxpython/docs/wxGUI.html

@@ -70,7 +70,8 @@ configuration and management); on a Mac, the GRASS functions menu is at the
 top of the screen.
 
 <center>
-<br><img src="wxGUI_layer_manager.jpg" border="1"><br><br>
+<br>
+<img src="wxGUI_layer_manager.jpg" border="1" alt="screenshot"><br><br>
 </center>
 
 The top left button of the toolbar opens a new <em>Map Display