Default test page has low-resolution image

[raboof]

The default test page has a 112x93-pixel image of Tux and a printer, blown up to 3.5x3cm on A4 paper - in other words, about 80 dpi. Typical printers can do way better than that.

Similarly, the color wheel seems to be a bitmap with 8-bit colors.

It might be nice to at least improve those images - or perhaps come up with a nicer test page altogether?