CKAN 2.8.11

Fixes:

• Fixes incorrectly encoded url current_url (#6685 <https://github.com/ckan/ckan/pull/6685>_)
• Check if locale exists on i18n JS API (#6698 <https://github.com/ckan/ckan/pull/6698>_)
• Add csrf_input() helper for cross-CKAN version compatibilty (#7016 <https://github.com/ckan/ckan/issues/7016>_)
• Fix not empty validator (#6658 <https://github.com/ckan/ckan/pull/6658>_)
• Use get_action() in patch actions to allow custom logic (#6519 <https://github.com/ckan/ckan/pull/6519>_)
• Allow to extend organization_facets (#6682 <https://github.com/ckan/ckan/pull/6682>_)
• Expose check_ckan_version to templates (#6741 <https://github.com/ckan/ckan/pull/6741>_)
• Allow get_translated helper to fall back to base version of a language (#6815 <https://github.com/ckan/ckan/pull/6815>_)
• Fix server error in tag autocomplete when vocabulary does not exist (#6820 <https://github.com/ckan/ckan/pull/6820>_)
• Check if locale exists on i18n JS API (#6698 <https://github.com/ckan/ckan/pull/6698>_)
• Fix updating a non-existing resource causes an internal sever error (#6928 <https://github.com/ckan/ckan/pull/6928>_)