Pull salt file references out of the states

def salt_refs(data):
    '''
    Pull salt file references out of the states
    '''
    proto = 'salt://'
    ret = []
    if isinstance(data, six.string_types):
        if data.startswith(proto):
            return [data]
    if isinstance(data, list):
        for comp in data:
            if isinstance(comp, six.string_types):
                if comp.startswith(proto):
                    ret.append(comp)
    return ret