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 
Does the `reversed` really have any effect here? Due to Smalltalk's order of message interpretation, this line could be read as
`aString splitBy: (',' reversed)`