error in citations.url constraint

[mdietze]

Trying to create a citation for the CLM technical manual http://www.cesm.ucar.edu/models/cesm1.0/clm/ and BETY's yelling at me that Url is not a valid URL. Use a schema-qualified URL. To use arbitrary strings, enclose them in parentheses. but I literally cut-and-pasted the URL from my browser and it looks completely normal, so I don't get why it's not a valid URL. I checked #230 and the URL in question should not be excluded, so there's probably a bug in the constraint.