Fixed #7064: Made DemicmalField validation support max_digits equal to decimal_places.

        decimals = abs(exponent)

        # digittuple doesn't include any leading zeros.

        digits = len(digittuple)

        if decimals >= digits:

        if decimals > digits:

            # We have leading zeros up to or past the decimal point.  Count

            # everything past the decimal point as a digit.  We also add one

            # for leading zeros before the decimal point (any number of leading

            # whole zeros collapse to one digit).

            digits = decimals + 1

            # everything past the decimal point as a digit.  We do not count 

            # 0 before the decimal point as a digit since that would mean 

            # we would not allow max_digits = decimal_places.

            digits = decimals

        whole_digits = digits - decimals

        if self.max_value is not None and value > self.max_value:

Traceback (most recent call last):

...

ValidationError: [u'Ensure that there are no more than 2 decimal places.']

>>> f.clean('-000.1234')

>>> f.clean('-000.12345')

Traceback (most recent call last):

...

ValidationError: [u'Ensure that there are no more than 4 digits in total.']

# Leading whole zeros "collapse" to one digit.

>>> f.clean('0000000.10') == Decimal("0.1")

True

>>> f.clean('0000000.100')

Traceback (most recent call last):

...

ValidationError: [u'Ensure that there are no more than 3 digits in total.']

# But a leading 0 before the . doesn't count towards max_digits

>>> f.clean('0000000.100') == Decimal("0.100")

True

# Only leading whole zeros "collapse" to one digit.

>>> f.clean('000000.02') == Decimal('0.02')

True

>>> f.clean('000000.002')

>>> f.clean('000000.0002')

Traceback (most recent call last):

...

ValidationError: [u'Ensure that there are no more than 3 digits in total.']

>>> f.clean('.002') == Decimal("0.002")

True

# DateField ###################################################################