This caused a 500 when sending a redaction due to a typo in a method
invocation.

Use a proper elastic directive to make the <textarea> resize dynamically.
Use an 'asjson' directive to turn an ngModel of a JSON object into a
formatted JSON string so it can be displayed on the textarea. Also, deep
copy the state events being displayed, else it actually alters the underlying
data structures when playing around with the JSON in the textarea!