'Determine whether or not the card is a record-valued keyword card.
If one argument is given, that argument is treated as a full card image
and parsed as such.  If two arguments are given, the first is treated
as the card keyword (including the field-specifier if the card is
intended as a RVKC), and the second as the card value OR the first value
can be the base keyword, and the second value the \'field-specifier:
value\' string.
If the check passes the ._keyword, ._value, and .field_specifier
keywords are set.
Examples
self._check_if_rvkc(\'DP1\', \'AXIS.1: 2\')
self._check_if_rvkc(\'DP1.AXIS.1\', 2)
self._check_if_rvkc(\'DP1     = AXIS.1: 2\')'

def _check_if_rvkc(self, *args):

    if (not conf.enable_record_valued_keyword_cards):
        return False
    if (len(args) == 1):
        self._check_if_rvkc_image(*args)
    elif (len(args) == 2):
        (keyword, value) = args
        if (not isinstance(keyword, string_types)):
            return False
        if (keyword in self._commentary_keywords):
            return False
        match = self._rvkc_keyword_name_RE.match(keyword)
        if (match and isinstance(value, (int, float))):
            self._init_rvkc(match.group('keyword'), match.group('field_specifier'), None, value)
            return True
        if (isinstance(value, string_types) and (value.find(':    ') > 0)):
            match = self._rvkc_field_specifier_val_RE.match(value)
            if (match and self._keywd_FSC_RE.match(keyword)):
                self._init_rvkc(keyword, match.group('keyword'), value, match.group('val'))
                return True
