title: How to set themes globally for ggplot2?
body: <p>I created a package with plenty of functions that generate ggplot plots.</p>
  
  <p>At the beginning, I used the default theme for all my plot functions (grey theme) but then I found the black and white theme to be more pleasant to the eye and developed my latest plot functions using that theme.</p>
  
  <p>Is there a way to set the ggplot2 theme globally, i.e. in one place, without having to modify all my plot functions each time I find a new theme I want to apply to all my plots?</p>