title: Read only first few lines of CSV (or any text file)
body: <p>I often come across larger datasets where I don't know what they actually contain. </p>
  
  <p>Instead of waiting for them to be opened in a conventional text editor or within the RStudio text editor, for example, I would like to look at the first few lines. </p>
  
  <p>I don't even have to parse the contents, scanning these first few lines will help me to determine what method to use. </p>
  
  <p>Is there a function/package for this? </p>