title: bar_plot ggplot: conflict between values on bar and x axis label
body: <p>I'm struggling with my code to create a barplot with ggplot2 in which I try to add <code>y</code> values on top of the bars, but without moving the labels of the <code>x</code> axis.
  <code>geom_text</code> works great to add values on the bars, but then I cannot adjust the <code>x</code> axis labels properly when rotated by 45˚ (i.e. the last letter of the label sticked to the axis).</p>
  
  <p>My data</p>
  
  <pre><code> dput(graph)
  structure(list(x = structure(1:9, .Label = c("AAAAAAAAAAAAA", 
  "BBBBBBBB", "CCCCCCCCCCCCCCCC", "DDDDD", "EEEEEEEE", "FFFFFFF", 
  "GGGGGGGGGGGGGGG", "HHHHHHHHHHHHHH", "IIIII"), class = "factor"), 
      y = c(1L, 5L, 10L, 1000L, 20L, 15L, 45L, 30L, 35L)), .Names = c("x", 
  "y"), class = "data.frame", row.names = c(NA, -9L))
  </code></pre>
  
  <p>My code:</p>
  
  <pre><code>graph &lt;- read.table("input.txt",header=T,sep=";")
  output &lt;- ggplot(graph,aes(x=x,y=y))+
      geom_bar(stat="identity")+
      geom_text(aes(label=y,y=(y+25)))+
      scale_x_discrete()+
      scale_y_continuous(limits=c(0,max(50 + graph$y)))+
      theme(axis.text.x=element_text(angle=45,vjust=0))
  print(output)
  </code></pre>
  
  <p>I cannot post an image of the output, but the plot looks fine except the tick marks of the <code>x</code> axis fit to the middle of the <code>x</code> labels instead of the last letter of the label. </p>