Workbench re-design settings dialog UI

[davemfish]

The main settings dialog is getting kind of long. Our current approach of stacking everything vertically might not be best once it forces people to scroll.

Something like vertical tabs for each section (language, logging, metadata, etc) that control a large main content area might be better.

We might want to consider other UI/UX design changes at the same time as this one, to try to consolidate all the changes within a single release.

Other issues include,

• WB: placement of "Open" button is confusing #1000
• Add a visual distinction between the top titlebar and the rest of the page #866
• The UI design for plugins
• The "clear recent runs" button might make more sense on the home tab, near the list of recent runs