installing languageserver on Ubuntu

[rpodcast]

We need a few system libraries to get languageserver installed due to dependencies:

• {curl}: libcurl4-openssl-dev
• {xml2}: libxml2-dev
• {openssl}: libssl-dev
• {httr}: Depends on {curl} and {openssl}
• {roxygen2}: Depends on {xml2}
• {lintr}: Depends on {xml2}