Compression Support in out_http plugin

[rockliffelewis]

Is your feature request related to a problem? Please describe.

Similar to #2047 , I would like to be able to generate compressed gzip HTTP output that would able to be transparently ingested by the in_http plugin so I can accomodate larger message sizes in a http based fluentd to fluentd setup.

Describe the solution you'd like

the http request should be sent with Content-Encoding: gzip headers set and the serialized message content should be gzip encoded

Describe alternatives you've considered

Unfortunately our enviroment makes using the forward plugin, which supports this type of setup much easier, hard for us to implement and HTTP suits us much better.

Additional context

No response