title: ggplot - get date label in Mon-yyyy format
body: <p>With a dataframe like below</p>
  
  <pre><code>data = data.frame(
    name=rep(c('Toyota', "Honda", "Nissan") ,each=4)
    ,date=c(rep(seq(as.Date("2016/1/1"), by = "month", length.out = 4),2),rep(seq(as.Date("2017/1/1"), by = "month", length.out = 4),1)),
    sales=sample(10:20, 12, replace=T)
    )
  </code></pre>
  
  <p>I want to plot a line graph of sales as below;</p>
  
  <pre><code>library(ggplot2)
  ggplot(data, aes(x=date, y=sales)) + geom_line(aes(color=name))
  </code></pre>
  
  <p>This gives me the x-axis labels as <code>2016-01</code> ... <code>2017-01</code> and so on.</p>
  
  <p><a href="https://i.stack.imgur.com/d1mdC.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/d1mdC.png" alt="Plot"></a></p>
  
  <p>I need to get the x-axis labels as <code>Jan-2016</code>, <code>Feb-2016</code> and so on.</p>