Named list of font names to be aliased with
fonts installed on your system. If unspecified, the R default
families "sans", "serif", "mono" and "symbol"
are aliased to the family returned by match_family().
If fonts are available, the default mapping will use these values:
| R family | Font on Windows | Font on Unix | Font on Mac OS |
sans | Arial | DejaVu Sans | Helvetica |
serif | Times New Roman | DejaVu serif | Times |
mono | Courier | DejaVu mono | Courier |
symbol | Symbol | DejaVu Sans | Symbol |