On Windows I was seeing some weirdness around finding RLock in the threading
module that originated here. I spent more time than I should have debugging,
but this fixes the problem and lets me at least load remotefilelog properly
on Windows. If it matters, this was Python from python.org, version 2.7.14.
Some of this demandimport disable goo was cargo-culted from the in-core
highlight extension. We should probably look into globally ignorning
some of the pkg_resources and friends.