series +setbranch requires invalid cvs urls

[Curtis Hovey]

Using series +setbranch to import a branch, setting the type to 'cvs' and url to :pserver:<email address hidden>:/cvsroot/tidy, the form errors:
    ":pserver:<email address hidden>:/cvsroot/tidy" is not a valid URI

I pondered and removed the leading ":" and got this error:
    The URI scheme "pserver" is not allowed. Only URIs with the following schemes may be used: http, https

Surpised, I did add a 'http://' prefix, and got this error:
    A username may not be specified in the URI.

So I removed the credentials and submitted and was very surprised to see it accepted.
http://tidy.cvs.sourceforge.net:/cvsroot/tidy is not a valid cvs url.

I had to edit the import to provide the original URL to fix the import.