Change link to tutorial in README

The tutorial that was previously linked to doesn't show up in the sidebar of typescriptlang.org/docs/ anymore.

The "TypeScript in 5 minutes" tutorial is essentially the same tutorial, but does show up in the sidebar and the docs overview.

By linking to this, the user that clicks through knows where they end up on the docs page, instead of being lost on the "Quick Tutorial" that they can't find again, except through this README.

README.md

@@ -42,7 +42,7 @@ with any additional questions or comments.
 
 ## Documentation
 
-*  [Quick tutorial](https://www.typescriptlang.org/docs/tutorial.html)
+*  [TypeScript in 5 minutes](https://www.typescriptlang.org/docs/handbook/typescript-in-5-minutes.html)
 *  [Programming handbook](https://www.typescriptlang.org/docs/handbook/basic-types.html)
 *  [Language specification](https://github.com/microsoft/TypeScript/blob/master/doc/spec.md)
 *  [Homepage](https://www.typescriptlang.org/)