[Docs] Update Indices Exists section

Author: gmarz

docs/contents/nest/indices/indices-exists.markdown

@@ -10,16 +10,19 @@ menuitem: indices-exists
 
 Used to check if the index (indices) exists or not.
 
-## Unknown index 
+## Examples
 
-	var r = this.ConnectedClient.IndexExists("yadadadadadaadada");
-	Assert.False(r.Exists);
-	//404 is a valid response in this case
-	Assert.True(r.IsValid);
+### Fluent Syntax
 
-## Known index 
+	var result = client.IndexExists(i => i.Index("myindex"));
 
-	var r = this.ConnectedClient.IndexExists("nest_test_data");
-	Assert.True(r.Exists);
+### Object Initializer Syntax
 
+	var request = new IndexExistsRequest("myindex");
+	var result = client.IndexExists(request);
 
+## Handling the Index Exists response
+
+`result` in the above examples is an `IExistsResponse` which contains a bool property `Exists`.
+
+One thing to note is that if an index does not exist, Elasticsearch will return a `404`.  In this case, a `404` is a valid response and thus `result.IsValid` will be `true`.