CHANGES_NEXT_RELEASE

[cygnus-ngsi][Docker] Add grouping rules files for multiagent (#1533)
[cygnus-ngsi][NGSIOrionSink] Create NGSIOrionSink (#1447)
[cygnus-common] Update httpclient dependence to 4.3.6 due to a vulnerability
[cygnus-ngsi][KafkaSink] Use lower_case option to build topics (#1468)
[cygnus-ngsi][NGSIDynamoDBSink] [bug] Southeast regions are bad coded (#1448)
[cygnus-common][CommonUtils][debug] Modify that CommonUtils#getTimeInstant can accepts the ISO8601 format with offset like 2018-01-02T03:04:05+09:00 (#1517)
[cygnus-ngsi][Docker] Add new env var  CYGNUS_MONITORING_TYPE
[cygnus-ngsi][KafkaSink] Using global connection to zookeeper instead of creating one each time an event arrives