Example improvements

[LogicalError]

The example / test suite should, imho, also contain the following additional things

• see fonts in multiple sizes (especially the small fonts are important to see, since those are the trickiest)
• mixing different font sizes on the same line, to see that they're all placed on the baseline correctly
• text moving horizontally, so we can see if text subpixel rendering is working correctly / smoothly

[memononen]

These would be good additions.

There are some tricks to improve the the smaller sizes, like snapping the Y, which I left as "let's do it when needed".