Way to override returned reference itself

[kohanis]

It is, on the whole, a suggestion. Currently, there is no way to override the reference itself in a method like ref T fn()
This implementation adds an optional parameter out RefResult<T> __resultRef (out is a requirement as it is called immediately after the patch and nulled), where delegate ref T RefResult<T>()
I don't have a user-case for this, but someone might have one

// On second thought, out requirement is unnecessary, ref is okay

[kohanis]

Lack of documentation is intentional until acceptance of feature itself is confirmed

[pardeike]

Very nice work. I added two comments, please verify. And beside the comments, I think we can go and add some documentation (make sure you don't edit html files but appropiate markdown in /Harmony/Documentation and all docfx annotations of course.

[kohanis]

Added docs(Never been good at it, hope it's understandable), new test + initial reset + restructured. Lifted out requirement

[pardeike]

I will pull this and clean up any documentation if necessary later. Excellent work, much appreciated and great timing to get this into the next big release.

[kohanis]

Actually, I was wrong. This could have been achieved through prefix with skip and/or passthrough postfix. I completely forgot about them. But now it's too late to delete... Apologies

EDIT: Well, I suppose new method is a little more optimal