Handle unparseable JSON response for API requests

[stensrud]

worker-1 (err): SyntaxError: Unexpected end of input
worker-1 (err):     at Object.parse (native)
worker-1 (err):     at Request.callback [as _callback] (/srv/sites/prod/worker/gameengine/node_modules/geckoboard/lib/api-request.js:14:29)
worker-1 (err):     at Request.self.callback (/srv/sites/prod/worker/gameengine/node_modules/geckoboard/node_modules/request/request.js:187:22)

Getting these in our production environment. This pull request wraps a try/catch around JSON parsing to avoid uncaught errors crashing the server.

[holm]

With todays problems, this happened again: https://geckoboard.statuspage.io/incidents/ltjvjyt9yts0

Would be good to fix this so meaningful error messages can be seen in case of issues with the api.

[t-o-m-]

@stensrud thanks for taking the time to look into this issue. A fix has now been merged and released (see #18 - we like our code to have tests, hence the new PR).

cc @holm

[holm]

Thanks for fixing this. I would recommend though that you either log the response body or include it in the error. These things can be very hard to debug when all you have is "Unparseable response" in the error logs. Usually there will be some information in the body, such as a "Gateway failure" or something like that, which helps you understand the nature of the problem.