include comments in cothread JSON response.
include link in comment JSON.
render link urls in thread view.
add getId wrapper to thread model and move test to shared tests.
catch nil url in link before_validation callback.
mock embedly api to avoid making lots of requests in tests.
generate urls dynamically in link factory to avoid failing uniqueness validation.
specify attributes to return from as_json for comment json response.
override serializable_hash instead of as_json to ensure that json configuration applied to nested models.
update all gems and fix tests to work with capybara 2.0.
needed to get jasmine specs to pass.