Revert "If a shortened URL begins with http://, don't include it in the shortened url. Saves 7 characters, which is pretty awesome for 140 character max length notices."

This reverts commit e2848eb862.

Downstream consumers of our notices (such as Friendfeed, Facebook, etc) don't have sophisticated URL detection, so a notice that reads: "check out ur1.ca/1" won't be linked. So the http:// prefix is
mandatory.

lib/util.php

@@ -1414,9 +1414,6 @@ function common_shorten_url($long_url)
 
     curl_close($curlh);
 
-    if(substr($short_url,0,7)=='http://'){
-        $short_url = substr($short_url,7);
-    }
     return $short_url;
 }