converts powershell script GUI strings representations to
        True/False/None

def _powershell_script_order_reverse_conversion(cls, val, **kwargs):
        '''
        converts powershell script GUI strings representations to
        True/False/None
        '''
        if val.upper() == 'Run Windows PowerShell scripts first'.upper():
            return 'true'
        elif val.upper() == 'Run Windows PowerShell scripts last'.upper():
            return 'false'
        elif val is 'Not Configured':
            return None
        else:
            return 'Invalid Value'