std.experimental.logger formal review round 3

[Dicebot via Digitalmars-d]

On Monday, 10 November 2014 at 11:46:34 UTC, Robert burner 
Schadek wrote:
> After your last reply we haven't done anything else.
>
> I would merge his idea, but there is pushback from your side. 
> Anyway, this idea would not break the api. So I don't think it 
> is a blocking change, IMO.

kk, I'll try contacting him via e-mail if Martin does not return 
to this thread soon enough :) This proposal may not break API 
directly but it greatly affects how derivative libraries are 
supposed to be designed and distributed so I'd prefer to nail it 
down immediately.

There are also some more @safe changes need, I hope to provide 
another branch with those soon enough (~tomorrow)