Form fields now remember their current type if the type is deleted. This
allows for fields to properly format their values if set after the form
has been changed to the 'submit' type.
Changes:
May now use underscored method names
form.field is replaced by form['fields']
form.get_fields no longer accepts use_dict parameter, it always
returns an OrderedDict now
form.set_fields will accept either an OrderedDict, or a list
of (var, dict) tuples as before.
Setting the form type to 'submit' will remove extra meta data
from the form fields, leaving just the 'var' and 'value'
Setting the form type to 'cancel' will remove all fields.