r.shaded.relief manual: clarify azimuth direction

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@60167 15284696-431f-4ddb-bdfa-cd5b030d7da7

raster/r.shaded.relief/r.shaded.relief.html

@@ -16,7 +16,7 @@ however, any raster map layer can be named.
 (a value between 0 and 90 degrees).
 
 <li>The <b>azimuth</b> of the sun in degrees to the east of north
-(a value between 0 and 360 degrees).
+(a value between 0 and 360 degrees; clockwise from north).
 
 <li>The scaling parameter, which compensates for a different 
 horizontal <b>scale</b> than vertical scale. If <b>scale</b> is a