Detecting a Promise bug in v8 (node 0.11 and 0.12).

v8 bug: https://code.google.com/p/chromium/issues/detail?id=371021
examples: https://gist.github.com/getify/bd11ccf1eff2efdac0fb

The test isn't currently a failing test, because the v8 Promise implementation doesn't support subclassing, which we already detect - but this way we'll explicitly detect both bugs.
Remove unnecessarily strict define.amd check. Closes #249