[patch] Option to collapse fieldset if empty

[Chris Beaven]

​Collapsable FieldSets are cool. But I wanted them to be able to collapse only if the fields within the field set are blank.

Usage example:

    fields = (
        (None, {
            'fields': ('name', 'date')
        }),
        ('Extra info', {
            'classes': 'collapse collapse_empty',
            'fields' : ('note',)
        }),
    )

[Chris Beaven]

Oops, was mixed spaces and tabs. Now just spaces.

[James Bennett]

This can be accomplished already with the js option in the current admin, and should be equally easy in newforms-admin.