[tlu] Yosemite workaround

[Maxwell, Adam R]

Okay, I'm almost certain this is an Apple bug. The people here have some workarounds, but the bottom line is that environment variables are broken in Yosemite.

http://stackoverflow.com/questions/24022582/osx-10-10-yosemite-beta-on-git-pull-git-sh-setup-no-such-file-or-directory/

https://github.com/Homebrew/homebrew/issues/29843

As an aside, I use execve(2) to run child processes, and these duplicate variables don't appear to be in the sanitized environment that I pass…so there's no way that I can see to even work around the problem in my code.

Adam