WIP: Use global as root if available (for node)

@searls - Can you advise on how to write a test for this? Looks like all your tests are running via lineman in a browser. Do we need to setup a separate grunt task that runs in node? Or is there a way we can fake "global" in the lineman spec? (Which, it seems like no, since that fake would have to be available at the time jasmine-stealth is loaded...)

Also, I can't get the tests to run in my fork (says "0/0"), but they run fine in the manta-frontend node_module instance.