Parse the Redis optional replication section redis_replication measuremet

[adamflott]

Parse the Redis replication nodes into individual pieces (ip, port, offset, lag) instead of a single string

Required for all PRs:

• Signed CLA.
• [N/A] Associated README.md updated.
• Has appropriate unit tests.

[glinton]

Would you document the new redis_replication measurement in the readme? thanks

[adamflott]

@glinton done

[glinton]

Thanks, can you also update theses to use the new format:

### Metrics
- measurement1
  - tags:
    - tag1 (optional description)
    - tag2
  - fields:
    - field1 (type, unit)
    - field2 (float, percent)

+ measurement2

[adamflott]

@danielnelson @glinton I believe I addressed all the feedback, please review.

[glinton]

In the future, once a review has started, please refrain from force-pushing as we don't always have time for a compete re-review. thanks

[adamflott]

Any update? The code is ready. Also, is 1.13 the appropriate target? I feel this is a minor change and could likely be included in the 1.12.x line

[danielnelson]

Thanks @adamflott, sorry this will need to go out in 1.13 since we try to make as few changes as possible to the release branches to avoid introducing new bugs.