[bndtools] Effective view to show merged properties?

[kriegfrj]

As noted earlier, I like the effective view.

One thing I think we should consider is showing in the Effective view the results of the property merging. So if I had:

a.bnd:

-runrequires.a: bundle.a

b.bnd:

-include: a.bnd
-runrequires.b: bundle.b

... then the effective view would be:

-runrequires: bundle.a, bundle.b

The Provenance whould then reveal where in a.bnd and b.bnd those definitions were from. If it might be useful, it could also name the original pre-merged property name alongside the file name.