Added simple examples with R code to "9 - Julia is fast.ipynb" (in a gist)

[jmcastagnetto]

Just in case it is useful, using your code in: https://github.com/JuliaAcademy/Introduction-to-Julia/blob/main/9%20-%20Julia%20is%20fast.ipynb, I added a couple of small bits to benchmark R.

See the gist: https://gist.github.com/jmcastagnetto/fce3cad5856517250ad1cdc468d49865