v.what.rast manual: fix wording

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@59329 15284696-431f-4ddb-bdfa-cd5b030d7da7

vector/v.what.rast/v.what.rast.html

@@ -1,8 +1,9 @@
 <h2>DESCRIPTION</h2>
 
-<em>v.what.rast</em> reads the raster value for each point in the vector map
-and updates <b>column</b> in the vector attribute table by this value. The
-column should be type number (integer, float, double, ... ).
+<em>v.what.rast</em> retrieves raster value from a given raster map for each point
+stored in a given vector map. It can update a <b>column</b> in the linked vector
+attribute table with the retrieved raster cell value or print it. The column type
+needs to be numeric (integer, float, double, ...).
 <p>
 If the <b>-p</b> flag is used, then the attribute table is not updated
 and the results are printed to <tt>stdout</tt>.