Create plugin logstash-filter-transducer

Hi,
to create the https://github.com/purbon/logstash-weather-demo I had the necessity to actually break one event into several others, my situation was not possible, or at less I was not aware how to do it, with the current plugin set.

Basic use case is: From a given event that include a set of columns of interest, this plugin will build a new event per column, with the column of interest and the rest of columns not involved (not of interest). Like this we avoid having to rework data formats that are column oriented into a raw oriented one.

Link to the actual repo: https://github.com/purbon/logstash-filter-transducer
rubygems.org: https://rubygems.org/gems/logstash-filter-transducer

/cheers

Review the stated use case and the linked logstash-filter-transducer repository and RubyGems package. Determine whether the existing plugin should be integrated into Logstash, with acceptance criteria for splitting one event into multiple events while retaining non-selected columns. The issue names no Logstash file, entry point, or test to run.

Written by the indexing model from the issue text.