Let bunyan EPIPE errors silently fail

[benoitkoenig]

Related to https://uphold.atlassian.net/browse/BKO-2611

This PR intends to fix the issue raised on bunyan here: trentm/node-bunyan#491.

[fixe]

2>&1

[benoitkoenig]

@fixe I have tested your suggestion, but I can see 2 flaws with it:

• 2>&1 needs to be documented, and the other developers I asked told me that they did not know this solves the issue. This is also something we need to explain to new devs and remember to do systematically, adding unnecessary overhead.
• The process do not shut down systematically, and I still need to do a ps to check if I need to kill my node processes.
  @rbrtribeiro told me that there had been a discussion about this, but I don't know what was said so please feel free to share with me any concern.