Merge from Gnus git master

Merge from Gnus git master

2014-02-04 Lars Ingebrigtsen <larsi@gnus.org>
 * calendar/parse-time.el (parse-time-iso8601-regexp)
 (parse-iso8601-time-string): Copied from `url-dav' so that we can use
 it more generally.

2014-02-01 Lars Ingebrigtsen <larsi@gnus.org>
 * net/dns.el (network-interface-list): Define for XEmacs.

2014-01-31 Magnus Henoch <magnus.henoch@gmail.com>
 * net/dns.el (dns-servers-up-to-date-p): New function to see whether
 the network interfaces changed.
 (dns-query): Use it to flush the data.