std::run::Process::new() should take &[&str] instead of &[~str]

[metajack]

Right now you have to clone everything into an array instead of just passing pointers. It would be nice if it did the cloning behind the scenes if it really must be done, or better yet, avoid it altogether.

[metajack]

nominating production ready

[huonw]

This could probably be <S: Str>(..., &[S], ...), so that it can be called with &[~str] and &[&str] (etc) without having to create a new vector.