[yt-dev] Ghost zone pull request

[Matthew Turk]

Hi all,

I put up a PR for much improved ghost zone filling (particularly for
FLASH data!) that I'd appreciate a set of eyes on:

https://bitbucket.org/yt_analysis/yt/pull-request/54/improve-ghost-zone-generation-speed

Sam tested and sees that for some particular hierarchies there's a
slight slowdown as a result, but I think the improvement where it
applies will be worth that.

Thanks,

Matt