title: Adding title to ggsurvplot
body: <p>I would like to add title to ggsurvplot. Here is my code:</p>
  
  <pre><code>library(survival)
  library(survminer)
  
  fit &lt;- survfit(Surv(time, status) ~ sex, data = lung)
  ggsurvplot(fit, data =lung, main = "This is title")
  </code></pre>
  
  <p>It generates plot, but without title. If add <code>risk.table = TRUE</code>, then I get title on top of risk table, but not the main plot. </p>
  
  <pre><code>library(survival)
  library(survminer)
  
  fit &lt;- survfit(Surv(time, status) ~ sex, data = lung)
  ggsurvplot(fit, data =lung, main = "This is title", 
             risk.table = TRUE)
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/5vT2c.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/5vT2c.png" alt="ggsurvplot title"></a></p>
  
  <p>Any idea how to fix it?</p>