Support for "code" Markdown

[asolisc]

Hi Mr. Wilke,

First of all, thank you so much for the amazing ggtext! Certainly an amazing step in the right direction. I was trying to insert a "code" markdown in the title of the ggplot2 but apparently, ggtext doesn't support it yet?

Please find below the reprex.

Best, Alexis

library(ggtext)
library(tidyverse)

mpg %>% 
  ggplot(mapping = aes(x = displ)) +
  geom_bar(fill = "#13364C") +
  labs(
    title = "This is a `geom_bar()` plot"
  )  +
  theme(
    plot.title = element_markdown()
  )
#> Error: gridtext has encountered a tag that isn't supported yet: <code>
#> Only a very limited number of tags are currently supported.

^{Created on 2020-10-11 by the reprex package (v0.3.0)}

[clauswilke]

See #53.