Add a command to disable a rule for a single line

[jpsim]

For example:

// swiftlint:disable:next force_cast
let forceCastNoWarning = NSNumber() as! Int
let forceCastWithWarning = NSNumber() as! Int

Although I'm not convinced on the naming. Maybe // swiftlint:disable:X where X is an integer number of lines for which to disable the rule?

It would make it more convenient to temporarily disable rules for occasional violations.

[segiddins]

Why not just allow putting it at the end of the line, like rubocop does?

[jpsim]

Why not just allow putting it at the end of the line, like rubocop does?

so // swiftlint:disable rule_name would start a region if preceded by whitespace, but start and close a single-line region otherwise?

[segiddins]

Yeah. Not necessarily saying it's better, and it might clash with the line length rule

[richellis]

+1 for the suggestion about putting it at the end of the line. Perhaps an abbreviated syntax to mitigate line length issues, such as //sl: rule_name

[mpurland]

+1 for this suggestion

[jpsim]

Done in #292.