[phobos] Silent failure of std.container unittests

[Walter Bright]

Sean Kelly wrote:
>
>
> How about this... since unit tests are run after static ctors are run, the behavior of whether to throw an AssertError or report and continue can be a run-time configurable option.

Frankly, I don't think a configurable option is a good idea. Druntime 
has a lot of user configurability, and as far as I can tell, absolutely 
none of it has ever been used. It just adds complexity, both to the code 
and the documentation.