for 1.0 Release
---------------

* hub: cleanup Elasticsearch Forwarder
* hub: add support for Elasticsearch 5.x and 6.x
* hub: cleanup Piwik/Matomo Forwarder
* hub: implement clean shutdown
* hub: send ACK/NACK on Pipe Interface
* hub: harmonize command line options and add config file
* hub: add config parameter to limit fields of GeoIP lookup
* hub: sanitize/minimize User Agent Info

beyond 1.0
----------

* drop batch importer???
* how to handle NaN values form batch importer like flumotion-rrd?
* should we allow floats for client-count, bytes-sent etc.?
* address issues with python-twisted dropping messages when transmit buffer is full
* move common code of python-twisted based importer to seperate module
* fix wrong usage of twisted