fix(readme): add link to latest client lib

Author: rhajek

README.md

@@ -4,6 +4,8 @@
 [![codecov.io](http://codecov.io/github/influxdata/influxdb-java/coverage.svg?branch=master)](http://codecov.io/github/influxdata/influxdb-java?branch=master)
 [![Issue Count](https://codeclimate.com/github/influxdata/influxdb-java/badges/issue_count.svg)](https://codeclimate.com/github/influxdata/influxdb-java)
 
+### Note: This library is for use with InfluxDB 1.x. For connecting to InfluxDB 2.x instances, please use the [influxdb-client-java](https://github.com/influxdata/influxdb-client-java) client.
+
 This is the Java Client library which is only compatible with InfluxDB 0.9 and higher. Maintained by [@majst01](https://github.com/majst01).
 
 To connect to InfluxDB 0.8.x you need to use influxdb-java version 1.6.