NIFI-6649 - added separate query interval configuration for observati…

[YolandaMDavis]

…on queries

NIFI-6649 - documentation update

This PR allows users to configure query interval for predictions separately from prediction interval (e.g. predict 1 hour into the future using 3 mins of prior observations).

A new field was added in nifi.properties to support this:

nifi.analytics.query.interval (default is 3 minutes)

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Enables X functionality; fixes bug NIFI-YYYY.

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[mattyb149]

+1 LGTM, verified the settings are separate and being used appropriately. Thanks for the improvement! Merging to master