Improve Settings Page style

[Kittyfisto]

The current "Settings" page is incredibly ugly and doesn't into into the newer style anymore.
There's too many settings on just the one page => Spread the settings apart from each other with a simple
vertical tab-panel (take inspiration from Visual Studio | Resharper Options Panel: Vertical tabs on the left, settings on right).
In this first version, only a small amount of categories is necessary, the page can be enhanced with more categories and features when the need arises for it in later versions.