Fixed broken external link.

wiki/src/contribute/design/HTP.mdwn

@@ -27,9 +27,9 @@ us with supposedly accurate time information.
 Home-made research [[demonstrated|todo/authenticate_time_servers]]
 that NTPv4's server authentication features do not fit our usecase
 yet. Using it is the long term goal but in the meantime we decided to
-use [HTP](http://www.clevervest.com/twiki/bin/view/HTP).
+use [HTP](http://www.vervest.org/htp/).
 
-[HTP](http://www.clevervest.com/twiki/bin/view/HTP) is not really a
+[HTP](http://www.vervest.org/htp/) is not really a
 protocol, but uses a feature from HTTP, aka web traffic. According the
 specifications of HTTP/1.1 (RFC 2616) a web server needs to put a
 timestamp in a response to a web browser request. In web browsers you