Maximum History Lookback For Data Feed Providers

[DerekMelchin]

Expected Behavior

We document the maximum lookback for history requests and warm-up from each data feed.
If the API has information, we link to it (since it may change).

Actual Behavior

Undocumented for most of the brokerage data feeds, IQFeed, and Polygon.

Checklist

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• I have confirmed that this is not a duplicate issue by searching issues