Fix #2529: explicit protection package #3651

[Dicebot via Digitalmars-d-announce]

On Wednesday, 20 August 2014 at 14:36:59 UTC, Kagamin wrote:
> As I see on the realistic example of datetime, which is BIG, we 
> only need to split it into a flat set of files without an 
> overly deep package hierarchy.

We _may_ split it into flat set files (solving only part of the 
problem) but it is desirable to have a deeper package hierarchy. 
Package hierarchy is not just an encapsulation tool, it is also a 
great way to simplify navigation and finding needed modules - 
something that Phobos is current terrible at exactly because of 
flat hierarchies.