Preview of color settings

[lijon]

When changing color settings and syntax color settings, it would be nice if the preview displayed at the bottom of the dialog did update with the changed colors.

[jleben]

The reason why this has not been done yet is that the current settings infrastructure doesn't support this, without sever refactoring.

Instead, I think it would be acceptable if there is an Apply button, which would apply all the settings without closing the dialog. This way one could previe color settings in the currently open document behind the settings dialog.

[jleben]

There's now an Apply button.

However, it might look weird that the font updates immediately, while the rest of the settings needs an "apply" to show in the preview. Actually, I would just remove the preview editor, but we need some code to see the current font choice on.
Opinions?

[jleben]

There's now an Apply button. However, it might look weird that the font updates immediately, while the rest of the settings needs an "apply" to show in the preview. Actually, I would just remove the preview editor, but we need some code to see the current font choice on.

I've now completely removed the code editor from the editor configuration panel - also because that conflicted with code editor development for the purpose of split views.

I propose:

1. to show the currently selected font with a simple one-line text
2. to implement colors preview by applying the colors to text and background of items in the color selection list

[jleben]

Font and color configuration panels are now merged into one.
Both font and color preview is provided in the panel.