title: Add whiskers (horizontal lines) to multiple boxplots
body: <p>I need to add whisker (or horizontal lines) to my multiple box-plots. </p>
  
  <p>You can find my dataset here: <a href="https://dl.dropboxusercontent.com/u/70196097/dataset.txt" rel="nofollow">link to data is broken...</a></p>
  
  <p>In other words, I am plotting three variables (Mat, Ita, and Log) divided by Gender (F and M), in order to compare their box plots. I need to add an horizontal line at the end of both vertical lines in each box plot. </p>
  
  <p>I am using ggplot2 package and the code I am using so far is (this code allows me to create the box plots as I need them, I only need to add the horizontal lines):</p>
  
  <pre><code>ggplot(newdata,aes(x=variable,y=value)) + 
    geom_boxplot(aes(fill=Gender)) + 
    xlab("Subject") + 
    ylab("Quiz score") + 
    ggtitle("Boxplots for quiz score and gender") + 
    scale_fill_manual(values=c("pink","lightblue"),labels=c("Female","Male")) + 
    theme(plot.title = element_text(face="bold"))
  </code></pre>