[MERGE] Make 'ls' aware of views

[Ian Clatworthy]

Eduardo O. Padoan wrote:
> My first merge request, so I hope I've got everything right.
> This patch adds support for the 'ls' command to be aware of active
> filtered views.
> Currently when you do `bzr ls` and a view is active, all files will be
> listed. It should show only the files in the paths of the current
> view.
> Related to bug #332718.

Thanks for this. Taking a *quick* glance at the code, it looks pretty
close to right. It needs some tests added though before we can merge it
to bzr.dev:

1. Take a look at bzrlib/tests/blackbox/test_filtered_view_ops.py and
   add one for ls.

2. Take a look at bzrlib/tests/workingtree_implementations/test_views.py
   and add a test for check_path_in_view. (It's now a public function in
   the API so it needs an explicit test showing it works as advertised.)

bb:resubmit

Ian C.