Don't call logging.basicConfig if logging is already configured (#775).
Will not call logging.basicConfig if there is a root logger,
tornado logger or tornado.application logger.

Updated patch to reflect comments about tests and method privacy.
Correct example variable, use consistant quoting
Merge pull request #971 from gmr/logging-patch

Don't call logging.basicConfig if logging is already configured (#775). Replaces #887
Merge commit 'c2a25a'

* commit 'c2a25a':
  Correct example variable, use consistant quoting

Closes #972
Remove inaccurate IOLoop logging test cases.
Move _setup_logging to BaseIOLoop and use it in asyncio and twisted implementations.
Improved extensibility of LogFormatter

* refactored code separating coloring logic
* allow full line customization of the format
* possibly faster operation
Rename "normal" to "end_color" in log format strings.

When not colorizing, use empty strings instead of two copies of "normal".

Update docs.
Add trollius (py2 backport of asyncio) to tox config.

This passes the twisted integration tests but currently has some issues
with pycurl.
Update release notes for 3.2.0b2
Set version number to 3.2b2
Replace redundant dict.get() with [].
Add a link to the Stack Overflow 'tornado' tag from the docs.
Now that pycurl 7.19.3 with py3 support is out, add it to tox/travis.
Pin pycurl on travis to <7.19.3, removing it from py3.x.

SSL issues prevent pycurl 7.19.3 from being installed on travis.
Fix shell quoting in travis config.
Finalize 3.2 release notes
Set version number to 3.2.
Update README.rst to match docs/index.rst.
Bump version number to 3.3.dev1