Clearly list system dependencies in documentation

[harmongray]

Description of issue:

I think it would be an small QoL improvement for this package to clearly list the system dependencies.

While it may not be an issue on Windows, this is a common issue on Linux R packages.

I used the remotes::install_github("mdneuzerling/getsysreqs") package to list them clearly:

 [1] "git"                  "pandoc"               "make"                
 [4] "libssl-dev"           "libfreetype6-dev"     "libfribidi-dev"      
 [7] "libharfbuzz-dev"      "libfontconfig1-dev"   "libxml2-dev"         
[10] "libgit2-dev"          "zlib1g-dev"           "libcurl4-openssl-dev"
[13] "libjpeg-dev"          "libpng-dev"           "libtiff-dev"         
[16] "libicu-dev"          

This has been an issue visible elsewhere on the web for newer R Linux users, but it has been specifically referenced in issue #2464.

While not something that is hard to debug, it could shave off 5-10 minutes off a development install of R on Ubuntu and follows common practice for other packages, such as bspm and the R V8 web assembly engine, that are more geared towards Linux developers.

Solution:

Listing the packages for their distribution method is a good addition to the documentation, i.e.:

sudo apt install git pandoc make libssl-dev libfreetype6-dev libfribidi-dev libharfbuzz-dev libfontconfig1-dev libxml2-dev libgit2-dev zlib1g-dev libcurl4-openssl-dev libjpeg-dev libpng-dev libtiff-dev libicu-dev

I know nobody likes when people raise documentation issues, but I really do think it would be a small but appreciated smoothing of the process for Linux users.