[Getdp] solving trivial example using edge elements

[William McLean]

> > apparently, the boundary conditions are not applied as you want (from 
> > the file edge_elts.pre, I see that zero is assigned to all the edge 
> > elements on the boundary). Now, I don't know how to apply these BC... 
> > (and I'm interested)
> 
> 
> I made a quick try : I remove the assign constraint and I weakly apply 
> the BC on the boundary
> 
> It works


Thanks Olivier.  Your email made me realise that the boundary condition
is not sensible mathematically.  I am still trying to come up with
a good alternative. 

Bill McLean