Add a way to allocate huge array in Box without creating it on stack first

[singalen]

Box<huge array> has a known problem: it creates the value on the stack first.

try_new(t: T) also need to consume the value from somewhere - and that would be from stack.

Is it possible to add an API to create an uninitialized array in Box, and not allocate its value on stack first?

Thank you!