[#1193] Deprecate helpers.get_action()

Fixes #1193
Merge branch 'master' of github.com:ckan/ckan into 1193-deprecate-get-action-helper-second-try
[#1193] Move long deprecation message to changelog

Also add "deprecated" to docstring, needed to prevent warnings and test
fails.
[#1193] Improve doc on how to deprecate functions
[#1740] Support ignore_auth in group_ and organization_member_create

So we can call them from new-style action function tests, which depend
on ignore_auth.
Merge pull request #1727 from ckan/1193-deprecate-get-action-helper-second-try

[#1193] Deprecate helpers.get_action()
Update the complete route for "promoted-image.jpg"
Merge branch '1740-group-and-org-member-create-support-ignore-auth'
Merge branch 'patch-1' of https://github.com/tlacoyodefrijol/ckan into tlacoyodefrijol-patch-1
Add missing colon
Merge branch 'tlacoyodefrijol-patch-1'
Upgrade minified jquery to 1.10.2, for issue #1750
[#1750] Upgrade minified jquery to 1.10.2
Merge pull request #1762 from yhteentoimivuuspalvelut/1750-upgrade_minified_jquery

Upgrade minified jquery to 1.10.2, for issue #1750