Install libxml2

[cagancayco]

A few major R packages are dependent on xml2, which is a binding to libxml2.

[nmagee]

@cagancayco does this apply to any particular environment choice or all three? No worries either way, just want to be sure.

[cagancayco]

Definitely for RStudio. Tidyverse was complaining about xml2/libxml2. Not sure about the others though.

[nmagee]

Okay, good to know. Yeah herein lies the problem (so common with R but also with py) where OS packages are needed to support language packages.

[nmagee]

@cagancayco would it be easier if we drew up a short list of the most common packages for analysis and just pre-installed them anyway -- dependencies and all? I'm thinking of dplyr, tidyverse, ggplot2, tidyr, plotly, etc.?