Revision 1831908

Shelving: implement 'svn status' for a shelf.

The interface uses a special form of changelist name, 'svn:shelf:SHELFNAME',
to request operating on a shelf.

Example:

  $ svn st --cl svn:shelf:foo
  --- Changelist 'svn:shelf:foo':
  A       add.txt
  MM      mod.txt
  D       del.txt

TODO: specialize the command-line syntax and output format to say 'shelf'
and hide the 'svn:shelf:' prefix.

* subversion/include/svn_client.h
  (svn_client_shelf_version_status_walk): New.

* subversion/libsvn_client/shelf.c
  (wc_status_unserialize): Rename the unused pool parameter.
  (status_read): Fill in the changelist name as 'svn:shelf:SHELFNAME'.
  (shelf_status_baton_t,
   shelf_status_visitor,
   shelf_status_visit_path,
   shelf_status_walk): Allow starting the walk at a given top relpath.
  (wc_status_baton_t,
   wc_status_visitor,
   svn_client_shelf_version_status_walk): New.
  (shelf_paths_changed,
   svn_client_shelf_apply,
   svn_client_shelf_export_patch): Adjust callers (top relpath = "").

* subversion/libsvn_client/status.c
  (shelf_status,
   shelves_status): New.
  (svn_client_status6): Run status on any requested shelves, before the
    main WC.

* subversion/tests/cmdline/shelf_tests.py
  (shelf_status): New test.
  (test_list): Run it.