Configure the sink

You need to pass in a configuration instance when registering the sink. In the constructor you need to pass in at least a uri where the Elasticsearch server is running. This is in the form of http://localhost:9200 for example.

You can also pass in multiple addresses and the internal Elasticsearch.net library will use all the addresses and connect to the first one responding. When this instance fails to respond it will automatically switch to the other ones listed. Use this to provide higher availability for your Elasticsearch endpoints.

TODO; more to come