EmailEntry seems to be always required

Even when I specifically set force_input=False, the field is required.

So when I render:

import alfred3 as al

exp = al.Experiment()

exp += al.Page(name="email")
exp.email += al.EmailEntry(name="email", leftlab="Email", force_input=False)

exp += al.Page(name="next_page")

and click on "Next" without filling out the email field, I get a validation message:

ctreffe / alfred

EmailEntry seems to be always required #144