Theme support and improved settings

Just a quick update to show off some of the new Themes and Settings:

The new "Settings" page. Each option opens a new settings screen. The previous Settings screen was a bit of a jumble with many things listed in a bit of a random order. It also looked a bit too "plain" and hopefully the new icons and the lighter indented text make it a better.

The preference to set a Theme. There are three currently coded.

The main bookmarks list rendered using the new "Light" theme. Note the rendered button bar across the top and a bit more colour in the results themselves.

For the people who asked to be beta testers, I might be ready to send something out tomorrow.

For all others, barring any bugs, this should be published in a few days.