Add a bias to the weighting of buysell orders

[scoobie-bot]

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Desired Behavior

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I want to ...
Be able to change the balance of % in the buysell strategy.
i.e. spread=1%
Set buys at 0.4% below mid
Set sells at 0.6% above mid

Impact

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The desired behavior will allow me to gradually increase the price

Feature Suggestion

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Specification

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