Update CDN URL for the new 0.6.0 release
Fix QUnit dep to 1.14.0 to ensure we're testing the right thing (since qunit globals are fixed in 1.15.0)
Only use one anonymous function so the scope of `this` is the top-level, enabling a user to define `this` by wrapping the loglevel code in a function and invoking it with apply(desiredScope);