Enable High Resolution Metrics with the Cloudwatch output

[devinsba]

Feature Request

Per the recent blog post: https://aws.amazon.com/blogs/aws/new-high-resolution-custom-metrics-and-alarms-for-amazon-cloudwatch/

AWS now supports second resolution metrics when a PutMetricData request includes a new optional parameter StorageResolution set to 1

Proposal:

Add a config option to allow for writing data at this resolution

Current behavior:

The client uses the standard behavior with 1 minute resolution metrics

Desired behavior:

The metrics created and updated by telegraf will use high resolution when configured to

Use case: [Why is this important (helps with prioritizing requests)]

Cloudwatch Alarms now support reacting in 10s when using 1s resolution metrics. This allows our infrastructure to be more reactive to change.

[radykal-com]

I'd like to take care of this as I need it :)