Fix TypeScript ESLint warning

[kunalkundaje]

When generating a TypeScript project with linting enabled, the current set of dependencies resolves to typescript: 2.9.1 and typescript-eslint-parser: 15.0.1, which are not fully compatible with each other and lead to the following warning message when linting:

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WARNING: You are currently running a version of TypeScript which is not officially supported by typescript-eslint-parser.

You may find that it works just fine, or you may not.

SUPPORTED TYPESCRIPT VERSIONS: ~2.8.1

YOUR TYPESCRIPT VERSION: 2.9.1

Please only submit bug reports when using the officially supported version.

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This PR upgrades typescript-eslint-parser to ^16.0.0 and explicitly upgrades typescript to ^2.9.1 to fix the warning.

[kunalkundaje]

Looks like this was updated in 7b90fdc
Closing this PR.