Add a bit about RequestsCookieJar to Cookies section

docs/user/quickstart.rst

@@ -416,6 +416,19 @@ parameter::
     >>> r = requests.get(url, cookies=cookies)
     >>> r.text
     '{"cookies": {"cookies_are": "working"}}'
+    
+Cookies are returned in a :class:`~requests.cookies.RequestsCookieJar`,
+which acts like a ``dict`` but also offers a more complete interface,
+suitable for use over multiple domains or paths.  Cookie jars can
+also be passed in to requests::
+
+    >>> jar = requests.cookies.RequestsCookieJar()
+    >>> jar.set('tasty_cookie', 'yum', site='httpbin.org', path='/cookies')
+    >>> jar.set('gross_cookie', 'blech', site='httpbin.org', path='/elsewhere')
+    >>> url = 'http://httpbin.org/cookies'
+    >>> r = requests.get(url, cookies=jar)
+    >>> r.text
+    '{"cookies": {"tasty_cookie": "yum"}}'
 
 
 Redirection and History