Cleaned up javascript code

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | 2.3
| Fixed tickets | n/a

1. Reused variable `emailList` which is best practice and easier to read
2. Removed `return false`. There is no use for it in this context and many consider it to be bad use as well. For example: http://fuelyourcoding.com/jquery-events-stop-misusing-return-false/
I'm not sure of the benefit removing the `return false` since it's more intuitive and easy to read than `e.preventDefault()` and have in this context the same role... :o