Update typescript to version 2.1.5 🚀

[greenkeeperio-bot]

Hello lovely humans,

typescript just published its new version 2.1.5.

State	Update 🚀
Dependency	typescript
New version	2.1.5
Type	devDependency

This version 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 typescript.
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.

Do you have any ideas how I could improve these pull requests? Did I report anything you think isn’t right?
Are you unsure about how things are supposed to work?

There is a collection of frequently asked questions and while I’m just a bot, there is a group of people who are happy to teach me new things. Let them know.

Good luck with your project ✨

You rock!

🌴

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The new version differs by 2569 commits (ahead by 2569, behind by 90).

• 2dbc531 Update LKG
• c26f402 Merge pull request #13277 from Microsoft/fix13276
• f412e10 Fix the emit when jsx attribute expression is empty
• 32cec58 Update LKG
• f330a7e Merge pull request #13220 from Microsoft/mergeMaster1229
• cc306f6 Aggregate flags for ExpressionWithTypeArguments
• bf7c51c Do not report helper module errors in ambient contexts for Rest helper
• 708f9e5 Fix UMD header to work with r.js
• 3eabf97 Updated baselines
• b155b68 Improve SourceMap emit for down-level async functions
• 150463e tsserver should use newline provided by the host (#13185) (#13186)
• dde8411 Update LKG
• 5f720c2 Merge pull request #13138 from Microsoft/mergeMaster1222
• 50288d9 Check trace enabled befoe tracing
• 2cf9979 Merge pull request #13105 from Microsoft/Fix12921

There are 250 commits in total. See the full diff.

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This pull request was created by greenkeeper.io.

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