Add fonts packages

I started having some trouble running window managers because they were segfaulting on missing fonts.
I've added extra package for fonts (which I found in a fork of your repo).

Meanwhile I've made two other modifications:
1. Moved the package declaration to attributes. This way people using the cookbook can override/provide more packages to install. Even more unsupported OSs.
2. Changed the attribute keys form symbols to strings by recommendation of a lint tool called foodcritic