Update tslint to the latest version 🚀

[greenkeeper]

Version 4.2.0 of tslint just got published.

Dependency	tslint
Current Version	4.1.1
Type	devDependency

The version 4.2.0 is not covered by your current version range.

Without accepting this pull request your project will work just like it did before. There might be a bunch of new features, fixes and perf improvements that the maintainers worked on for you though.

I recommend you look into these changes and try to get onto the latest version of tslint.
Given that you have a decent test suite, a passing build is a strong indicator that you can take advantage of these changes by merging the proposed change into your project. Otherwise this branch is a great starting point for you to work on the update.

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Release Notes

4.2.0

• [new-rule] no-string-throw (#1878)
• [new-rule] no-empty-interface (#1889)
• [new-rule] interface-over-type-literal (#1890)
• [new-rule] callable-types (#1891)
• [new-rule] no-void-expression (#1903)
• [new-rule-option] ban-single-arg-parens added to arrow-parens (#1893)
• [bugfix] prefer-const handles destructuring arrays (#1894), destructuring objects (#1906), and forward references (#1908)
• [bugfix] Don't error for misplaced braces for 'else' in one-line rule (#1866)
• [bugfix] no-shadowed-variable now identifies shadowed for iterator (#1816)
• [bugfix] object-literal-key-quotes now includes function names (#1874)
• [bugfix] error when EOF comes after disable-next-line comment (#1902)

Not sure how things should work exactly?

There is a collection of frequently asked questions and of course you may always ask my humans.

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Your Greenkeeper Bot 🌴