Re: Unchecked arrays

[cblake]

As a trivial correction, @Stefan_Salewski wrote `add()` in one spot where he 
meant `addr`, but `add` is totally within the "safe zones" of Nim and even 
applies to `seq[T]` types when you cannot `setLen` ahead of time. (`setLen` is 
faster when you can use it, though.) Just trying to block potential confusion.