title: RStudio - changing default code chunk
body: <p>In RStudio, when I insert a new code chunk in my .Rmd file (Code>Insert chunk, or Ctrl-Alt-I), by default it has the header <code>{r}</code>. I'd like to have it instead default to the knitr option <code>{r, message=F}</code>, which I find makes for nicer final report outputs. Is there a way to change the default code header in RStudio? Thanks!</p>