Add ability to get/set HTTP response reason phrase in RequestHandler and HTTPResponse
simple_httpclient: Report errno and reason for connection errors.

Previously, this reported "Connection closed" for everything. This change
adds the exception info: HTTP 599: [Errno 61] Connection refused
Do not remove empty GET/POST parameters
Add binary_form argument to get_ssl_certificate.

The default form contains only basic information; the binary form is more
complete.
Reorganize IOStream tests and run them in both regular and ssl mode.

In the process, discover a quirk of the server-side SSL handshake and
a possible bug with ssl in pypy.
Allow calls to SSLIOStream.write while the connection is in progress.

Skip fast-path writes while connecting, and rework the interaction
between base class and subclass to avoid the possibility of doubly-wrapped
sockets.

Closes #587.
When closing an HTTPConnection, also clear a circular reference to self.

This reference could cause garbage collection of the connection object
to be delayed.

Closes #586.
Merge remote-tracking branch 'evanj/master' into merge
Fix test for pre-2.7 assertions
Release note updates
Make authdemo's logout less confusing.

Closes #376.
Make the openid claimed_id available in OpenIDMixin

This should be used as a persistent identifier for the user
since it is the only field guaranteed not to change.

Closes #568.
Refactor template namespace from render_string to its own method.

This method may be overridden as an alternative to overriding render_string
and adding to kwargs, or may be used directly to render templates
without going through render_string (as when templates are constructed
directly; see https://github.com/facebook/tornado/issues/564)
Fix template errors with empty blocks.

Emits a "pass" statement in every generated block whether it's empty or not;
I verified with the disassembler that the unnecessary pass statements
don't generate extra bytecodes.

Closes #546.
Release note updates
Don't let autopep8 rewrite all the lines longer than 80 chars.
Autopep8 cleanups.
Run twisted tests in a temporary directory so they don't leak temp files.

This mainly affected the unix socket tests.
Fill in missing docs and other minor doc updates.
Document all available application settings.