Improve url-http debugging

* lisp/url/url-http.el (url-http-parse-headers): Output the
headers we receive in the debug output.
* lisp/url/url-vars.el (url-extensions-header): Remove useless header.

lisp/url/url-http.el

@@ -589,6 +589,13 @@ should be shown to the user."
   (url-http-debug "url-http-parse-headers called in (%s)" (buffer-name))
   (url-http-parse-response)
   (mail-narrow-to-head)
+  (when url-debug
+    (save-excursion
+      (goto-char (point-min))
+      (while (not (eobp))
+        (url-http-debug "Response: %s"
+                        (buffer-substring (point) (line-end-position)))
+        (forward-line 1))))
   ;;(narrow-to-region (point-min) url-http-end-of-headers)
   (let ((connection (mail-fetch-field "Connection")))
     ;; In HTTP 1.0, keep the connection only if there is a

lisp/url/url-vars.el

@@ -396,7 +396,7 @@ Should be one of:
 (defvar url-lazy-message-time 0)
 
 ;; Fixme: We may not be able to run SSL.
-(defvar url-extensions-header "Security/Digest Security/SSL")
+(defvar url-extensions-header nil)
 
 (defvar url-parse-syntax-table
   (copy-syntax-table emacs-lisp-mode-syntax-table)