Simplify Chrome loader + fix toggle injection location

I started this branch to look into simplifying the loading of the Chrome extension. It now :fire:s all of the `MutationObserver` craziness and fires the loader on `(window).load` like the Safari extension (which uses "End scripts" in the Extension builder, same thing?).

In the process, I noticed that the toggle switch is injected in a position that only works for your own profile page and other people in your org. I changed this which fixes #25.