intellisense typeroots for jsconfig.json

Suggestion

Add the typeRoots property for jsconfig.json like tsconfig.json

Use Cases

In an Asp.net Core project , there are no intellisence for view.cshtml file's <script> when my type definition file put in wwwroot/@typings

Examples

/aspnetcoreproject
   | wwwroot
       |@typings
       |tsconfig.json
   |Views
        |Home
            |index.cshtml    (can not find the type definition files)
   |jsconfig.json

Checklist

My suggestion meets these guidelines:

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.

Compare how jsconfig.json and tsconfig.json handle configuration properties, then trace the existing typeRoots handling. Verify the change against the Asp.net Core example so type definitions under wwwroot/@typings are available to script code in index.cshtml.