Update man 5 page

Changes 'orientation' to 'default_orientation' to match commands.c

sway/sway.5.txt

@@ -36,13 +36,13 @@ The following commands may only be used in the configuration file.
 	+
 	See **sway-bar**(5) for details.
 
+**default_orientation** <horizontal|vertical|auto>::
+	Sets the default container layout for tiled containers.
+
 **set** <name> <value>::
 	Sets variable $name to _value_. You can use the new variable in the arguments
 	of future commands.
 
-**orientation** <horizontal|vertical|auto>::
-	Sets the default container layout for tiled containers.
-
 The following commands cannot be used directly in the configuration file.
 They are expected to be used with **bindsym** or at runtime through **swaymsg**(1).