Some proposed changes to the introductory section of the Python 2.7 What's New document. Key changes:

* I updated the Future of Python 2.x section to describe the status quo, rather than preserving the original speculation from 2010
* I added a new section to record the changes made in maintenance releases
* I moved the DeprecationWarning change down to its own section, since it is really independent of Python 2.7 being the last release

Open questions:

* the current wording makes it clear that while it's hard to get features backported, PEP 466 isn't necessarily a one time deal. I'm open to changing that to instead just describe PEP 466 as is, without saying anything about using the PEP process to get other changes backported
* I currently have the "New Features in Maintenance Releases" section near the top. Since it's hyperlinked from the "Future of Python 2.x" section anyway, perhaps I should move it towards the end instead?

It occurred to me while writing this that we'll potentially have an influx of conservative Python users reading the doc this year, as RHEL 7 and CentOS 7 become generally available, finally upgrading the default Python in that ecosystem to 2.7.