planning for 3.x release

[Carl Meyer]

Hi all,

There are a long list of unreleased bugs and small features slated for
release in the 2.x branch [1], so I'm planning to do a 2.4 release
pretty soon. If there's anything you've been wanting to submit a fix
for, now would be a great time to do it.

We've also accumulated a few potentially backwards-incompatible changes
in master [2], so I'm thinking ahead towards a 3.0 release before long.
I've labeled the issues that I definitely want to fix before releasing
3.0 [3] -- please comment on any other issues you're aware of that you
think will require significant backwards-incompatibility to fix that we
should consider fixing for 3.0.

Also, if you have a nunjucks-using project and you are willing to try
upgrading to the latest 2.x branch or master, and report back on whether
it causes any problems to your project, that would be super-helpful!
You'll need to run `npm browserfiles` from a git checkout to generate an
updated browser build in the `browser/` directory.

Thanks,

Carl


[1]
https://github.com/mozilla/nunjucks/blob/master/CHANGELOG.md#2x-unreleased
[2]
https://github.com/mozilla/nunjucks/blob/master/CHANGELOG.md#3x-unreleased
[3]
https://github.com/mozilla/nunjucks/issues?utf8=%E2%9C%93&q=is%3Aissue+is%3Aopen+label%3A3.x