Set global font options (rather than specifying body, column, header, etc invdividually)

[jthomasmock]

After a discussion with @rich-iannone I posted this issue.

gt has easy and rich support for custom fonts which I love, but to change fonts across the entire table I believe the only way so far is to do the following (and if you wanted to change things like the title you'd also need to specify further targets):

library(gt)
suppressPackageStartupMessages(library(dplyr))

ggplot2::mpg %>% 
  head() %>% 
  gt() %>% 
  gt::tab_style(
    style = list(
      cell_text(font = "Fira Mono")
    ),
    locations = list(
      cells_body(gt::everything()),
      cells_column_labels(gt::everything())
  
  ))

^{Created on 2020-05-15 by the reprex package (v0.3.0)}

It'd be great if there were options to:

• Set a global/table level font
• Override sections optionally with the above formatting (cell body, columns, title, etc)
• Clearly understand WHERE fonts are allowed to be imported from IE:
  • System Installed fonts
  • Imported web fonts
  • Integration w/ font packages (extrafont, systemfonts, gridtext, etc)

Some ideas about supporting/loading fonts via:

• systemfonts
• thematic
• gridtext

Tagging @apreshill for her interest as well.

[zrodriguez89]

On a related note, I have seen similar requests regarding setting other stylistic changes to a table. For example, if I want to easily change all of the borders to black instead of the default gray as stated elsewhere.

#176 (comment)

I was actually digging through the code for when gt is initialized to see if I can find where the color is set. This could at least allow when creating the object to set a color for example.