title: sample not working in sparkR session
body: <p>I installed Spark-1.4.0 from source on my machine, running fedora 21, kernel 4.0.5-200.fc21.x86_64 and I ran install-dev.sh on
  the spark-1.4.0/R directory. Now when I start 'sparkR' on my terminal everything starts up normally, I get to the command prompt and do the following :</p>
  
  <pre><code>&gt; sample(seq(1,10),size=4)
  Error in sample(seq(1, 10), size = 4) : unused argument (size = 4)
  </code></pre>
  
  <p>My question is why 'sample' throws this error in the SparkR console. This works in a regular R session, i.e. </p>
  
  <pre><code>&gt; sample(seq(1,10),size=4)
  [1]  1 10  4  2
  </code></pre>