This change will theme the fast scroll thumb in relation to the current theme.
Comment formatting
Merge pull request #300 from adneal/fastscroll

Theme the fast scroll thumb in relation to the current theme
Remove custom set progress drawables.
Set progress bar styles globally, add new darker variant for light theme.
Merge branch 'less-bright-scrollbars' into beta
Merge remote-tracking branch 'upstream/beta' into beta