Update INSTALLATION.md (exercism#316)

* Update INSTALLATION.md

Updated the Installation page as per the discussion held.

Made changes by 
1. Adding the link R Extension for Visual Studio Code
2. Updated the link to include tidyverse library

* Update INSTALLATION.md

I spotted an old typo as I was about to merge.

---------

Co-authored-by: colinleach <[email protected]>

docs/INSTALLATION.md

@@ -3,11 +3,16 @@
 ## Install the R runtime
 Visit the [CRAN homepage](https://cran.r-project.org/). There you will find download links for Linux, Mac OSX, and Windows. Download and run the installer for your operating system.
 
-## Install the RStudio IDE
+## Install the RStudio IDE (Recommended)
 RStudio is a popular cross-platform integrated development environment (IDE) for programming in R (and also supports other languages like Python, JavaScript, and Markdown). Using RStudio will make writing your code solutions and running tests easier.
 
 Download and install the [current stable version of RStudio](https://www.rstudio.com/products/rstudio/download/). Or, alternatively, get the [preview version](https://www.rstudio.com/products/rstudio/download/preview/) of an upcoming release.
 
+## Install the Visual Studio Code extension for R (Alternative)
+The R extension for Visual Studio Code supports extended syntax highlighting, code completion, linting, formatting, interacting with R terminals, viewing data, plots, workspace variables, help pages, managing packages and working with R Markdown documents.
+
+Download and install the [current version of R extension](https://code.visualstudio.com/docs/languages/r)
+
 ## Install the R packages for running tests
 The test runner for the specs is the [`testthat`](https://github.com/hadley/testthat) library from Hadley Wickham, which is a popular choice for R package authors.
 
@@ -17,9 +22,9 @@ To install this library, type the following in your RStudio console (or wherever
 install.packages("testthat")
 ```
 
-While it is unlikely that you will _need_ to install packages to solve the exercism problems, you may want to bring in a general-purpose utility packages like [`magrittr`](https://github.com/smbache/magrittr) that suit your programming style. To install and load a package like `magrittr`:
+While it is unlikely that you will _need_ to install packages to solve the exercism problems, you may want to bring in a general-purpose utility package like [`tidyverse`](https://github.com/tidyverse/tidyverse) that suit your programming style. To install and load a package like `tidyverse`:
 
 ```{R}
-install.packages("magrittr")
-library(magrittr)
+install.packages("tidyverse")
+library(tidyverse)
 ```