Feature REQ: Support for "fields" Object

[lilgreenwein]

Starting with version 6.5, Splunk has added a top level object - parallel to "event" - called "fields". Reference:

http://dev.splunk.com/view/event-collector/SP-CAAAFB6

Right now the kafka-connect-splunk sink puts all consumed data under the "event" object. Adding support to populate the "fields" object (with JSON data of course) would enable the sink to specify indexed field extractions