Hercules DJ Control Starlight: Add EffectChain superknob control

[konstruktiv]

This adds controls for moving the metaknobs of all effects in the chain by holding the SHIFT button and turning the Bass/Filter knob.

[JoergAtGithub]

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[konstruktiv]

Done.

[acolombier]

Code LGTM!

Thanks for your contribution @konstruktiv and welcome to the team!