Make DMD emit C++ .h files same as .di files

[Jacob Carlborg]

On 2019-02-25 02:04, Manu wrote:

> Why wouldn't you do it in the same pass as the .di output?

* Separation of concerns
* Simplifying the compiler ("simplifying" is not the correct 
description, rather avoid making the compiler more complex)

I think the .di generation should be a separate tool as well.

-- 
/Jacob Carlborg