Fixed laziness of current_user in UI modules, and added tests for current_user. #820
Correctly handle EAGAIN when writing to PipeIOStreams

BaseIOStream._handle_write needs to catch IOError and OSError as
well as socket.error in order to handle EAGAIN when writing to a
PipeIOStream (which doesn't appear to raise socket.error when the
buffer is full).

This also provides consistency with the exceptions caught by
BaseIOStream._read_to_buffer.
Merge pull request #848 from SuprDewd/issue_820

Fixed laziness of current_user in UI modules, and added tests for current_user.
Merge pull request #851 from taguchimail/master

Correctly handle EAGAIN when writing to PipeIOStreams
Crude fix for issue #855: automatically initiate SSL handshake in SSLIOStream.
Perhaps this should be exposed as an option instead?
Add in Google OAuth2 support.
Fix up documentation for the class and the Sphinx reference.
Make poll timeout patchable.
Merge pull request #859 from schlamar/patch-1

Make poll timeout patchable.
Route all callback error logging in IOLoop through handle_callback_exception.
Clear the IOStream buffers on close even when there is no close callback.

Closes #828. (again)
RequestHandler sets its close callback on the HTTPConnection, not the IOStream.

Fixes a bug in which close callbacks would never be called for subsequent
requests on a reused connection.
Merge remote-tracking branch 'pitrou/issue855-ssl-auto-handshake'
Less crude fix for #855: only do anything for already-connected sockets.
Allow deleting all cookies on custom domains
Update ca-certificates.crt to the current Mozilla version.

This file was generated by downloading
https://mxr.mozilla.org/mozilla/source/security/nss/lib/ckfw/builtins/certdata.txt?raw=1
in a web browser to avoid the chicken-and-egg problem with mk-ca-bundle's
built-in downloading, and then running "mk-ca-bundle.pl -n".

Note that we were not affected by the recently-fixed curl bug
(https://github.com/bagder/curl/commit/51f0b798fa), but only because
it had been so long since we had updated this file.
Merge pull request #874 from skazhy/clear-all-cookies-custom-domain

Allow deleting all cookies on custom domains
Add comments for domain and path arguments to cookie-clearing methods.
Update next-release notes.
Document Windows support (or lack thereof).

Closes #871.