Export add integration test

This PR:

* Adds integration tests for the export functionality
* Tweaks a few things so that tests pass consistently. E.g.:
    * Sort dictionary keys to get consistent ordering from run to run
    * Use `items` in place of `iteritems` in upstart template for Python 3 compatibility
    * Apply fix from https://github.com/nickstenning/honcho/pull/102 so that we don't get spurious test failures that confuse things.