Allow the formHelper->label() to have default options

Ok, re-doing this request to the proper branch.

This allows any labels to have their default options set using a new option called 'labelDefaults'
It seems to me that 'label' is the only one missing this, as all other inputs have it.

I looked at the unit-tests for the formHelper, and I wasn't quite sure how to implement the tests, I can amend this commit with any tests, just advise me on the proper way to lay them out.