title: How to config an instance (folder) inside redis database
body: <p>I am using c# with StackExchange.Redis.
  I used something like this to connect : </p>
  
  <pre><code>    var client = ConnectionMultiplexer.Connect(_appSettings["Cache:Redis:Configuration"]);
      _database = client.GetDatabase(int.Parse(_appSettings["Cache:Redis:LockProcessDB"]));
  </code></pre>
  
  <p>and then I access the set / get commands via : </p>
  
  <pre><code>_database.StringSet(data.Key, data.Value, TimeSpan.FromSeconds(_ttl), When.NotExists, CommandFlags.None);
  ...
  </code></pre>
  
  <p>I now need to divide different "sections" in my data into different "folders" in the redis database.
  So instead of just setting values under DB 7, I want DB 7 to have a sub folder called : Documents and the values I am setting should be inserted under that folder. </p>
  
  <p>In the <code>Microsoft.Extensions.Caching.Distributed</code> for .net core solution they support in registering it like this :</p>
  
  <pre><code>services.AddDistributedRedisCache(options =&gt;
                  {
                      options.Configuration = ConfigUtils.Instance.Get("Redis_Config", "");
                      options.InstanceName = "Documents:";
                  });
  </code></pre>
  
  <p>which then directs my set commands into the "Documents" sub folder. 
  How do I achieve that with StackExchange.Redis?</p>