wibox.widget.systray: Update the property documentation.

lib/wibox/widget/systray.lua

@@ -148,7 +148,11 @@ end
 -- available space. Otherwise, any single icon has a size of `size`x`size`.
 --
 -- @property base_size
--- @tparam[opt=nil] integer|nil base_size The base size
+-- @tparam[opt=nil] integer|nil base_size
+-- @propertytype integer The size.
+-- @propertytype nil Select the size based on the availible space.
+-- @propertyunit pixel
+-- @negativeallowed false
 -- @propemits true false
 
 function systray:set_base_size(size)
@@ -162,7 +166,7 @@ end
 --- Decide between horizontal or vertical display.
 --
 -- @property horizontal
--- @tparam[opt=true] boolean horizontal Use horizontal mode?
+-- @tparam[opt=true] boolean horizontal
 -- @propemits true false
 
 function systray:set_horizontal(horiz)
@@ -176,7 +180,7 @@ end
 --- Should the systray icons be displayed in reverse order?
 --
 -- @property reverse
--- @tparam[opt=false] boolean reverse Display in reverse order.
+-- @tparam[opt=false] boolean reverse
 -- @propemits true false
 
 function systray:set_reverse(rev)
@@ -194,7 +198,9 @@ end
 -- visible on the primary screen. The default value is "primary".
 --
 -- @property screen
--- @tparam[opt=nil] screen|"primary" screen The screen to display on.
+-- @tparam[opt=nil] screen|nil screen
+-- @propertytype nil Valid as long as the `systray` widget is only being displayed
+--  on a single screen.
 -- @propemits true false
 
 function systray:set_screen(s)