[yt-users] mainline development is moving to yt 4.0 shortly

Hi folks, As a heads up, we're in the final stages of merging yt-4.0 into the branch that is presently called "master" on github. So if you are running off the mainline development, you will soon see this rather extensive change. You may need to install additional dependencies (notably unyt) but this should be handled by running "pip install -e ." in your yt directory. Once this is in, we'll work to update and edit PRs to retarget them. Most should not need much in the way of changes. Thanks to everybody who worked so hard to make this happen! -Matt