Commented some logging that could be '''very''' long, cuts -vv output size of a gtkd gl sample down 1.2GB by 3/4. Fixed wrong pointer type for multidimension "deep" slicing.

module tangotests.stdout2;

import tango.io.Stdout;

void main()
{
    Stdout.formatln("{} {} {}", "a", "b", 1.0);
}