r.viewshed manual cosmetics (fix paramater name, no backslashes to avoid GUI user confusion)

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@70382 15284696-431f-4ddb-bdfa-cd5b030d7da7

raster/r.viewshed/r.viewshed.html

@@ -88,7 +88,7 @@ Main memory usage: By default <em>r.viewshed</em> assumes it has
 500MB of main memory, and sets up its internal data structures so that
 it does not require more than this amount of RAM.  The user can set
 the amount of memory used by the program by setting the
-<b>memory_usage</b> to the number of MB of memory they would like to
+<b>memory</b> to the number of MB of memory they would like to
 be used.
 
 
@@ -179,8 +179,7 @@ above ground:
 
 <div class="code"><pre>
 g.region raster=elev_lid792_1m -p
-r.viewshed input=elev_lid792_1m output=elev_lid792_1m_viewshed \
-  coordinates=638728.087167,220609.261501 observer_elevation=5.0
+r.viewshed input=elev_lid792_1m output=elev_lid792_1m_viewshed coordinates=638728,220609 observer_elevation=5.0
 </pre></div>
 
 <div align="center" style="margin: 10px">
@@ -208,8 +207,7 @@ of a mountain:
 
 <div class="code"><pre>
 g.region raster=elevation.10m
-r.viewshed input=elevation.10m output=viewshed \
-  coordinates=598869,4916642 mem=800
+r.viewshed input=elevation.10m output=viewshed coordinates=598869,4916642 memory=800
 </pre></div>