[docs] Updated README with more usage examples. (#33)

Readme.md

@@ -14,6 +14,33 @@ var io = require('socket.io-emitter')({ host: '127.0.0.1', port: 6379 });
 setInterval(function(){
   io.emit('time', new Date);
 }, 5000);
+```
+```js
+// Different constructor options.
+
+//1. Initialize with host:port string
+var io = require('socket.io-emitter')("loaclhost:6379")
+// 2. Initlize with host, port object.
+var io = require('socket.io-emitter')({ host: '127.0.0.1', port: 6379 });
+// 3. Can use other node_redis compatible client eg; ioredis.
+
+var Redis = require("ioredis");
+var redis = new Redis();
+var io = require('socket.io-emitter')(redis);
+
+// Make the emitter works with redis clustered environment.
+var Cluster = new Redis.Cluster([
+    {
+        host: "localhost",
+        port: 6379
+    },
+    {
+        host: "localhost",
+        port: 6378
+    },
+]);
+var io = require('socket.io-emitter')(Cluster);
+
 ```
 
 ## API