Throw 404 for non-existent org for bulk_process

Fixes #1682
Merge branch 'master' into 1682-bulk-process
[#1682] Test that 404 is returned
[#1682] Fix pep8 issues
[#1878] make (org|group)_member_create return dictized membership
[#1873] setup template variables at start of member_new controller

If a validation error was thrown, then the template would be rendered
before these variables had been setup.
[#1682] clean up test code
Merge branch '1878-member_create_return_value' of https://github.com/joetsoi/ckan into joetsoi-1878-member_create_return_value
Merge branch 'joetsoi-1878-member_create_return_value'
Merge branch '1873-fix_group_member_controller' of https://github.com/joetsoi/ckan into joetsoi-1873-fix_group_member_controller
Merge branch 'joetsoi-1873-fix_group_member_controller'
[#1682] remove empty setup_class method
Merge branch '1682-bulk-process'
Merge pull request #1682 from ckan/1682-bulk-process

bulk_process page for non-existent organization throws Exception
Merge branch 'master' of github.com:ckan/ckan
Merge remote-tracking branch 'upstream/master'
Merge branch 'master' of https://github.com/clementmouchet/ckan