title: How to modify a legend title in a barplot with ggplot
body: <p>Imagine you have a simple dataset like this one:</p>
  
  <pre><code>   ive
        region   Edad
    1  Española   23
    2  Española   37
    3  Española   40
    4  Española   21
    5  Africana   29
    6  Española   42
    7   Europea   29
    8  Española   25
    9  Española   32
    10 Española   20
  </code></pre>
  
  <p>I am interested on performing a barplot for the variable <code>region</code> classifying by colour. So I created the following piece of code:</p>
  
  <pre><code> g1 &lt;- ggplot(ive, aes(x=reorder(ive$region, -table(ive$region)[ive$region])))
   g1 + geom_bar(aes(fill=ive$region)) + geom_text(stat='count',aes(label=..count..),vjust=-0.7) + xlab("")
  </code></pre>
  
  <p>But the legend of the plot displays <code>ive$region</code> and I want it to display a customized title.</p>
  
  <p>I am almost sure it is a silly question but I have been traying to solve it for 2 days and I dont find the way to do it.</p>
  
  <p>Thank you,
  Álvaro</p>