Support optional GZIP compression on outbound posts to splunk

[toscott]

Proposed changes

Hoping gzip compression here will help reduce our internet bandwidth consumption leveraging splunk hec to push events to splunk cloud.

Fixes #14

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

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[toscott]

New configuration param: gzip_compression true
Defaults false to maintain existing behavior.

[toscott]

Network transfer from splunk connect pods dropped around a factor of 10 after enabling this on our cluster.

[toscott]

Having some issues after a rebuild, making a couple tweaks and will push another commit.

[toscott]

Network transmit rate drop from log forwarders during rollout of compression.

[hvaghani221]

It looks good. Just wanted to know what was the impact on CPU and memory usage.

[toscott]

Baseline memory and cpu looks the same so far. I don't have detailed stats on these pods but my guess is the gc activity is slightly elevated.

[hvaghani221]

LGTM!