Declare @types/node as a dependency

[leonard-thieu]

Because the type definitions for gulp-typescript exposes declarations from @​types/node, @​types/node must be added as a dependency to ensure consumers will have it.

[ivogabe]

We've done that in the past, but this sadly causes that @types/node will automatically be added to all compilations using gulp-typescript.. See microsoft/TypeScript#11917. So I personally agree that this should be added, but it would break a lot of users.