Improve icons integration with {ggwordcloud}

[mitchelloharawild]

Using icons as masks for a word cloud is pretty cool. Currently you need to use rsvg::rsvg() to format the icons appropriately for the mask argument of ggwordcloud::geom_text_wordcloud_area(). Some simpler function would be nice for this:

library(ggwordcloud)
#> Loading required package: ggplot2
set.seed(42)
ggplot(
  love_words,
  aes(
    label = word, size = speakers,
    color = speakers
  )
) +
  geom_text_wordcloud_area(
  mask = rsvg::rsvg(charToRaw(format(icons::fontawesome$solid$hourglass))),
  rm_outside = TRUE
  ) +
  scale_size_area(max_size = 40) +
  theme_minimal() +
  scale_color_gradient(low = "darkred", high = "red")
#> Some words could not fit on page. They have been removed.

^{Created on 2021-03-12 by the reprex package (v0.3.0)}