wxGUI/dbmgr: update manual + add screenshot

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@54243 15284696-431f-4ddb-bdfa-cd5b030d7da7

gui/wxpython/dbmgr/g.gui.dbmgr.html

@@ -2,20 +2,34 @@
 <!-- meta page index: wxGUI -->
 <h2>DESCRIPTION</h2>
 
+The <b>Attribute Table Manager</b> is
+a <em><a href="wxGUI.html">wxGUI</a></em> compoment to query, edit,
+and manage attribute data for vector maps. The attribute table manager
+can be launched by clicking on icon <img src="icons/table.png"
+alt="icon"> in the toolbar. It's also available as a stand-alone
+module <em>g.gui.dbmgr</em>.
+
+<p>
 <em>Attribute table manager</em> allows to:
 
 <ul>
-  <li>Browse attribute data of vector map, perform SQL select
-  statements</li>
-  <li>Modify attribute data, insert new records to attribute table,
-  delete existing records</li>
-  <li>Highlight selected items in the Map Display Window</li>
-  <li>Extract selected items into a new vector map</li>
-  <li>Modify attribute table - add, drop, rename columns</li>
-  <li>Modify vector map DB connection settings - add, remove or
-  modify layers</li>
+  <li>browse attribute data of vector map, perform SQL select
+  statements;</li>
+  <li>modify attribute data, insert new records to attribute table,
+  delete existing records;</li>
+  <li>highlight selected items in the Map Display Window;</li>
+  <li>extract selected items into a new vector map;</li>
+  <li>modify attribute table - add, drop, rename columns;</li>
+  <li>modify vector map DB connection settings - add, remove or
+  modify layers.</li>
 </ul>
 
+<center>
+<br>
+<img src="dbmgr_frame.jpg" border="1" alt="Attribute Table Manager">
+<br><br>
+</center>
+
 <h2>SEE ALSO</h2>
 
 <em>