* Use jquery ui accordion for the field, and implemented an admin theme.
* Made the setting of configuration consistent with other form fields.
* ToggleComposteField->startClosed() has been deprecated in favour of
setStartClosed().
* Removed public access to the heading level, instead use getHeadingLevel()
or setHeadingLevel().
API CHANGE Removed several unsed JavaScript globals: sprintf(), Number.prototype.CURRENCIES, Number.prototype.toCurrency(), String.prototype.ucfirst(), jQuery.fn.clearFields(), jQuery.fn.clearInputs()
MINOR Removed prototype_improvements.js and jquery_improvements.js files, now contained in individual component code (or removed altogether)
