Add an "I agree to the terms of use" checkbox inside signup workflow.

(imported from commit 6d3320e71e189f4577da464fade9c8f7f5838f78)

zephyr/forms.py

@@ -17,6 +17,7 @@ class RegistrationForm(forms.Form):
     full_name = forms.CharField(max_length=100)
     password = forms.CharField(widget=forms.PasswordInput, max_length=100)
     domain = forms.CharField(max_length=100)
+    terms = forms.BooleanField(required=True)
 
 class HomepageForm(forms.Form):
     email = UniqueEmailField()