Deadlocks found when concurrently editing a closure tree hierarchy

[mceachen]

See http://stackoverflow.com/questions/14753906/deadlocks-when-concurrent-editing-a-closure-tree-hierarchy

[mceachen]

I've reproduced the error in my branch. Now to fix the issue...

[mchavarriagam]

I'm watching this issue, thanks!

[mceachen]

Fixed in v3.7.3