title: Redisson Client with Sentinel throws exception
body: <p>I'm using Redisson with below configuration to connect to Sentinel servers:</p>
  
  <pre><code>Config config = new Config();
  config.useSentinelServers().setMasterName("local")
              .addSentinelAddress("redis://localhost:26379", "redis://localhost:26380", "redis://localhost:26381");
  RedissonClient client = Redisson.create(config);
  </code></pre>
  
  <p>How ever when I run this code I get the below error creating the client:</p>
  
  <pre><code>Caused by: java.lang.IllegalArgumentException: port out of range:-1
      at java.net.InetSocketAddress.checkPort(InetSocketAddress.java:143)
      at java.net.InetSocketAddress.&lt;init&gt;(InetSocketAddress.java:224)
      at org.redisson.client.RedisClient.&lt;init&gt;(RedisClient.java:105)
      at org.redisson.connection.MasterSlaveConnectionManager.createClient(MasterSlaveConnectionManager.java:354)
      at org.redisson.connection.SentinelConnectionManager.&lt;init&gt;(SentinelConnectionManager.java:74)
      at org.redisson.config.ConfigSupport.createConnectionManager(ConfigSupport.java:258)
      at org.redisson.Redisson.&lt;init&gt;(Redisson.java:115)
      at org.redisson.Redisson.create(Redisson.java:154)
  </code></pre>
  
  <p>I wanted to know if I'm missing any thing in the redisson config or my sentinel servers are not configured well.</p>