Revert "labels and callbacks can be set when a field is created"

This reverts commit bb4b014b78e852297028595817414ceb5ceaa34e.

Signed-off-by: Blessing Osakue <iyoworks@gmail.com>

Conflicts:
	src/Iyoworks/FormBuilder/Form.php
fix merge

Signed-off-by: Blessing Osakue <iyoworks@gmail.com>