title: run describe schema using datastax cassandra driver 3.0
body: <p>when I am trying to run "describe keyspace keyspacename" command using datastax driver 3.0, it gives me an error </p>
  
  <pre><code>Exception in thread "main" com.datastax.driver.core.exceptions.SyntaxError: line 1:0 no viable alternative at input 'DESCRIBE' ([DESCRIBE]...)
  </code></pre>
  
  <p>How to run "describe keyspace keyspacename" command?</p>