Replace raw NetworkTables usage with LimelightHelpers

[jonahsnider]

Instead of directly accessing the Limelight through the NetworkTables API, we should update the version of LimelightHelpers we have and use that

We should also delete all the Limelight JSON related code, since we no longer are using that for vision

[saikiranra]

Why? Why can't we just do the nt calls like right now?

[jonahsnider]

Either way works for me. A handful of other parts of the code currently use LimelightHelpers, I think it'd be preferable if we stuck to one way of interacting with Limelight