[Pharo-project] windowsesque theme tweaks

Gary here's some tweaks I talked about (progressbar and tabbar fixed). After the attached is filedin, evaluate UIThemeXP setup then to see the tweaks try (progress bar) SystemProgressMorph example and (tab bar) UITheme exampleGroups also an odd thing that may hint at a bug, is the progress bar moves faster while you move the cursor. thanks. sw