Enhancement suggestion for std.bitmanip

[Baz]

I'd like to suggest some stuff to add to bitmanip: the concept of 
set of enums elements. The idea is simple: the enum members are 
stored in a set according to their rank.
So instead of OR-ing some consecutive values as usually done in C 
or C++ it's possible to do the same with the complex enums (based 
on a floating point type for example, or with some 
non-consecutives integer values).

I've written a module which demonstrates the concept. Tell me 
your thoughts about this idea. By the way, I'm a relatively a new 
comer in D, I've read on the wiki that there is a procedure to 
follow in to propose a new phobos module, but in this case I'd 
just like to propose some additions, not a new module, so be 
tolerant if I don't behave like expected...

The module which illustrates what I'd like to be added:
https://github.com/BBasile/BitSets

Rationale: The best argument I can give is that this is inspired 
by a Delphi language feature (the Sets) widely used. It keeps a 
logical relationship between the members of an enum in a single 
container (instead of having many fields related to the same 
context, it uses a single one). That's also very type-safe 
because it's based upon a template, the traits and a parametric 
struct.