add & document D. Greaves marquee patch, clean up render.c

docs/lcdproc-dev/language.docbook

@@ -348,7 +348,7 @@
 		  <left> <top> <right> <bottom> <direction> <speed> <text>
 	        </para>
 	        <para>
-                  direction can be "h" or "v".
+                  direction can be "h", "m" or "v".
 	        </para>
 	        <para>
                   speed is the number of movements per rendering stroke (8 times/second).

docs/netstuff.txt

@@ -194,7 +194,9 @@ widget_set #screen #id data
 			The speed is how many display frames to delay
 			between scrolling.  Each display frame is
 			1/8th of a second, by default.
-			Direction must be "h" or "v".
+			Direction must be "h" for horizontal, "m" for
+			marquee style horizontal or "v" for vertical
+			scrolling..
 			Positive speeds indicate frames per movement.
 			Negative speeds indicate movements per frame.