forms.field.URLField regexp for validating URL does not follow the RFC
|Design decision needed
|Patch needs improvement:
URLField validation in forms.fields checks that the supplied URL is well-formed before accepting it. The regexp used does not allow URLS of the form http://django/, where the assumption is that djanog is a host name opn a local server wihtout domain name. The relevant RFC (RFC3986) gives a regex that does allow this form of URL.