Merge branch 'ps/doc-http-empty-cookiefile'

What happens when http.cookieFile gets the special value "" has
been clarified in the documentation.

* ps/doc-http-empty-cookiefile:
  doc: update http.cookieFile with in-memory cookie processing

Author: gitster

Documentation/config/http.txt

@@ -107,12 +107,16 @@ http.cookieFile::
 	in the Git http session, if they match the server. The file format
 	of the file to read cookies from should be plain HTTP headers or
 	the Netscape/Mozilla cookie file format (see `curl(1)`).
+	Set it to an empty string, to accept only new cookies from
+	the server and send them back in successive requests within same
+	connection.
 	NOTE that the file specified with http.cookieFile is used only as
 	input unless http.saveCookies is set.
 
 http.saveCookies::
 	If set, store cookies received during requests to the file specified by
-	http.cookieFile. Has no effect if http.cookieFile is unset.
+	http.cookieFile. Has no effect if http.cookieFile is unset, or set to
+	an empty string.
 
 http.version::
 	Use the specified HTTP protocol version when communicating with a server.