cosmetics for NULL indication (to fix bad font size)

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@31481 15284696-431f-4ddb-bdfa-cd5b030d7da7

display/d.rast.num/description.html

@@ -23,6 +23,7 @@ The user is advised to set the current region to a relatively
 small area (i.e., less than 100 rows by 100 columns);
 otherwise, the individual cells being displayed will be small
 and the category value associated with each will be difficult to see.
+No data cells are indicated with "Null".
 
 <H2>SEE ALSO</H2>
 

display/d.rast.num/number.c

@@ -1,6 +1,4 @@
 /*
- * $Id$
- *
  ****************************************************************************
  *
  * MODULE:       d.rast.num
@@ -334,12 +332,12 @@ int draw_number (double number, int prec, RASTER_MAP_TYPE map_type)
 	  if(!G_is_c_null_value(&cell))
 	    sprintf(no,"%d",(int)number);
 	  else
-	    sprintf(no,"N");
+	    sprintf(no,"Null");
 	}else{
 	  if(!G_is_d_null_value(&dcell))
 	    sprintf(no,"%.*f", prec, number);
 	  else
-	   sprintf(no,"N");
+	   sprintf(no,"Null");
 	}
 	len = strlen(no);