worldmap-window: set scale to 0.85 on show

Set the scale to 0.85 because the game default scripts set
it to fullscreen scale each time. Additionaly, as the hook
is now in place, it is no longer required to manually run
the default functions when the map gets shown.

mods/worldmap-window.lua

@@ -34,16 +34,12 @@ module.enable = function(self)
       this.hooked = true
 
       HookScript(WorldMapFrame, "OnShow", function()
-        -- default events
-        UpdateMicroButtons()
-        PlaySound("igQuestLogOpen")
-        CloseDropDownMenus()
-        SetMapToCurrentZone()
-        WorldMapFrame_PingPlayerPosition()
-
         -- customize
         this:EnableKeyboard(false)
         this:EnableMouseWheel(1)
+
+        -- set back to default scale
+        WorldMapFrame:SetScale(.85)
       end)
 
       HookScript(WorldMapFrame, "OnMouseWheel", function()