New Issue Checklist

• I've Updated SwiftLint to the latest version.
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Feature or Enhancement Proposal

Please add a line_count option for vertical_whitespace_between_cases that accepts a non-negative integer value, with a default value of 1, which would replicate the current behavior.

Setting it to 0 would ensure no blank lines between cases (what I want). Setting to some other number allows for multiple blank lines between cases.