LongStackTraces still mutating bluebird global in latest release.

Hi, it appears the longStackTraces removal never made it's way onto npm. On a fresh npm i install that code is still there in version 3.0. Can you please publish the latest code? 

https://github.com/beardon/mws-api/commit/e10996128184e431af2c87fbddd454d60272d246