`DecimalField` storing an `<input type="text">` and no quantize/round

from flask.ext.wtf import Form
from wtforms import DecimalField
import decimal

class InputDecimal(Form):
    price = DecimalField('price', places=2, rounding=decimal.ROUND_HALF_EVEN)
    submit = SubmitField('Submit')

# When instantiated it stores text instead of a number

form = InputDecimal()
if form.validate_on_submit():
    print(form.price)
    print(form.price.data)

# the print at runtime
<input id="price" name="price" type="text" value="999.999">
999.999
# There is no rounding/quantize of the value.

Start at the DecimalField entry point and trace how its submitted value is converted and rendered; compare the behavior with the places and rounding arguments in the example. Check existing field tests and add coverage showing the expected numeric value and rounded output for 999.999 with two places.