Update #surfacespread desc

core/src/main/java/com/sk89q/worldedit/command/PatternCommands.java

@@ -377,7 +377,7 @@ public class PatternCommands extends MethodCommands {
 
     @Command(
             aliases = {"#surfacespread"},
-            desc = "Randomly change the position to another block on the surface",
+            desc = "Applies to only blocks on a surface. Selects a block from provided pattern with a given ranomized offset [0, <distance>). e.g. Use `#existing` to randomly offset blocks in the world, or `#copy` to offset blocks in your clipboard",
             usage = "<distance> <pattern>",
             min = 2,
             max = 2