When used with the Ruby on Rails unobtrusive scripting adapter (rails_ujs.js),
now prevents duplicate form submission when Unpoly attributes are mixed with [data-method] attributes.
When up.observe() is used with a delay of zero, the callback is invoked instantly (instead of
being invoked in the next animation frame).
Upgrading
If you're upgrading from an older Unpoly version you should load unpoly-migrate.js
to polyfill deprecated APIs.
Changes handled by unpoly-migrate.js are not considered breaking changes.
