Rename Data-Provider and Data-Feed

[Romazes]

Expected Behavior

See PR - click

These params were renamed:

• --data-provider -> --data-provider-historical (to retrieve data from the given historical provider)
• --data-feed -> --data-provider-live (the live data provider to use)

Should use new terminology in lean-cli.
These changes were implemented in:

• lean backtest
• lean optimize
• lean research
• lean live deploy

Actual Behavior

Datasets are using wrong command in examples.

Mention: --data-provider

IEX Cloud

Link

https://www.quantconnect.com/docs/v2/lean-cli/datasets/iex-cloud

Image

IQFeed

Link

https://www.quantconnect.com/docs/v2/lean-cli/datasets/iqfeed

Image

Polygon

Link

https://www.quantconnect.com/docs/v2/lean-cli/datasets/polygon

Image

Mention: data-feed

IQFeed

Link

https://www.quantconnect.com/docs/v2/lean-cli/live-trading/data-feeds/iqfeed

Image

Polygon

Link

https://www.quantconnect.com/docs/v2/lean-cli/live-trading/data-feeds/polygon

Image

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