Incorrect breadcrumb menu links

If you create a new `organization` type, the name of that type is reflected in the breadcrumb menu on the adding a new organization page; i.e. at http://my_site/publishers/new, the breadcrumb menu has:

home link icon / a link to /publishers / a link to /publisher/new#

if you create a new `group` type, the name _isn't_ reflected; at http://my_site/subjects/new, the breadcrumb menu has:

home link icon / a link to /group / a link to /group/edit/

- the link to /group should be /subjects
- the link to /group/edit/ should be /subjects/edit/

(additionally, this should be /subjects/new#, but I _think_ this is core CKAN so will raise an issue there)

For avoidance of doubt, I do have the following in `edit_base.html`:

{% set group = c.group_dict %}

Start with the breadcrumb markup in edit_base.html and reproduce the new organization and group pages at /publishers/new and /subjects/new. Compare the generated links; the group breadcrumb should use /subjects and /subjects/edit/, while the /subjects/new# behavior is noted as a separate CKAN issue.

Written by the indexing model from the issue text.