Add the rollback history command line option.

[raduom]

Provide a --rollback-history INT and a configuration setting for the PAB Webserver (named rollbackHistory) that controls how much history we retain for rollbacks.

If you don't need to test rollbacks, then setting the rollback-history to a lower value (I tested with 500) will greatly limit the amount of RAM that the PAB will consume. A value of 0 turns off this feature.

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• Branch
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  • Formatting, materialized Nix files, PNG optimization, etc. are updated
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[raduom]

I just thought of moving the option into a new Development section as this and the one in the next PR should probably not be used in production.