bpo-39242: Updated the Gmane domain into news.gmane.io (GH-17903)

diff --git a/Lib/nntplib.py b/Lib/nntplib.py
index 1b7e83a..9036f36 100644
--- a/Lib/nntplib.py
+++ b/Lib/nntplib.py
@@ -1107,7 +1107,7 @@
         nntplib built-in demo - display the latest articles in a newsgroup""")
     parser.add_argument('-g', '--group', default='gmane.comp.python.general',
                         help='group to fetch messages from (default: %(default)s)')
-    parser.add_argument('-s', '--server', default='news.gmane.org',
+    parser.add_argument('-s', '--server', default='news.gmane.io',
                         help='NNTP server hostname (default: %(default)s)')
     parser.add_argument('-p', '--port', default=-1, type=int,
                         help='NNTP port number (default: %s / %s)' % (NNTP_PORT, NNTP_SSL_PORT))
diff --git a/Lib/test/test_nntplib.py b/Lib/test/test_nntplib.py
index daa4a79..88c54f4 100644
--- a/Lib/test/test_nntplib.py
+++ b/Lib/test/test_nntplib.py
@@ -639,7 +639,7 @@
                     "\tSat, 19 Jun 2010 18:04:08 -0400"
                     "\t<4FD05F05-F98B-44DC-8111-C6009C925F0C@gmail.com>"
                     "\t<hvalf7$ort$1@dough.gmane.org>\t7103\t16"
-                    "\tXref: news.gmane.org gmane.comp.python.authors:57"
+                    "\tXref: news.gmane.io gmane.comp.python.authors:57"
                     "\n"
                 "58\tLooking for a few good bloggers"
                     "\tDoug Hellmann <doug.hellmann-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>"
@@ -1125,7 +1125,7 @@
             "references": "<hvalf7$ort$1@dough.gmane.org>",
             ":bytes": "7103",
             ":lines": "16",
-            "xref": "news.gmane.org gmane.comp.python.authors:57"
+            "xref": "news.gmane.io gmane.comp.python.authors:57"
             })
         art_num, over = overviews[1]
         self.assertEqual(over["xref"], None)