Feature Request

To better test TypeScript expectations, we should be able to utilise Microsoft's dtslint tool.

I've had a look at how it could be integrated into the repo and I've created a branch that adds a dtslint script and adds the dtslint-related configuration and type-only tests to the type-specs directory:

cartant/rxjs/tree/dtslint/type-specs

The dtslint script can be added to the Travis $FULL_VALIDATE configuration.

This looks to me to be a great tool. Thoughts?

I was thinking that the type tests currently used in the test suite could be pretty easily be brought across to dtslint - in which the expectations would be more robustly tested.

Additional context

• Microsoft/dtslint
• Testing Types: An Introduction to dtslint