Rendering/font size

Fonts have to be reinstalled in order to have a great font-size experience.
Run `CSSFontFormatter uninstallFonts` once - reinstallation should be triggered automatically on the next use of fonts.

Closes #99 
Of course, they will be different. Independent from that, I would like to suggest a size 2pt bigger. That's no solution for font designer but will lead to more readable websites.  

This could be achieved by using  `(family fontOfPointSize: (TextStyle pixelsToPoints: size + 2)))].` in the last line.