Log Message:
Changes 13.2.0:
* Twisted now includes a HostnameEndpoint implementation which uses IPv4 and \ 
IPv6 in parallel, speeding up the connection by using whichever connects first \ 
(the 'Happy Eyeballs'/RFC 6555 algorithm).
* Improved support for Cancellable Deferreds by kaizhang, our GSoC student.
* Improved Twisted.Mail documentation by shira, our Outreach Program for Women \ 
intern.
* twistd now waits for the application to start successfully before exiting \ 
after daemonization.
* SSL server endpoint string descriptions now support the specification of chain \ 
certificates.
* Over 70 closed tickets since 13.1.0.