We need to update json from 2.1.0 to 2.3.0 because of CVE-2013-0269.
This gem is used by Elasticsearch, Resque, Cucumber, and code coverage gems.
How to test: this update should be decently covered by automated tests. For sanity:
Post a new work with tags. Check that the work shows up on user and tag listings.
Check that subscribers of a work receive emails about its new chapters.
Leave kudos as one user (with JS enabled). Check that the work author receives the correct kudos notifications.