[FIX][BUG] Not displaying full URL in HTTPClient error message ( http, not ftp )

[Lex Spoon]

This method is for http downloads, not ftp or other URL's.  If you want
to download an arbitrary URL, do something like this:

	url asUrl retrieveContents 

Instead of making thi smethod handle more kinds of URL's, how about
adding a comment saying how that class Url should be used to get general
URL functionality?