title: Font family won't change in ggplot
body: <p>My plot works, except I'm not able to get the font family to change. It always stays with the default, even when I can other things to change like color, size, and justification.</p>
  
  <p>Here's my code:</p>
  
  <pre><code>ggplot(data = SeattleJuly17Data,
         aes(x = Price, y = SatisfactionScore, col = RoomType)) +
      geom_point() +
      xlim(0,500) +
      geom_smooth() +
      ggtitle("Satisfaction Trends by Price and Room Type") +
      theme(plot.title = element_text(family = "Calibri",
                                      size=15,
                                      color="Red",
                                      hjust = 0.5)) +
      xlab("Price per Night") +
      ylab("Guest Satisfaction Score")
  </code></pre>