made all keywords from question_start.pstpl available to question.pstpl. Also added new keywords:
{QUESTION_ID} - the UID for each question
{QUESTION_CLASS} - unique class for each question type
{QUESTION_MAN_CLASS} - class if question is mandatory
{QUESTION_INPUT_ERROR_CLASS} - class if there was user input error
{QUESTION_DISPLAY} - style attribute if question is conditional

question_start.pstpl keywords now available in question.pstpl:
{QUESTION_TEXT} - Text for the question
{QUESTION_HELP} - (survey admin defined) Help text for question
{QUESTION_MANDATORY} - mandatory identifier for question (usually *)
{QUESTION_MAN_MESSAGE} - mandatory message text
{QUESTION_VALID_MESSAGE} - validation message text

These changes are backwards compatible with older templates.