Database connection issues not handled gracefully

[errietta]

If the database configuration is incorrect, and the connection fails, the user will get a 500 error and the terminal will bring an unfriendly error message:

{"name":"error","length":97,"severity":"FATAL","code":"28P01","file":"auth.c","line":"285","routine":"auth_failed","isBoom":true,"isServer":true,"data":null,"output":{"statusCode":500,"payload":{"statusCode":500,"error":"Internal Server Error","message":"An internal server error occurred"},"headers":{"Content-Security-Policy":"connect-src 'self';default-src 'none';font-src 'self' https://fonts.gstatic.com;img-src 'self' data: https://www.google-analytics.com http://www.google-analytics.com;script-src 'self' 'unsafe-eval' https://www.google-analytics.com http://www.google-analytics.com;style-src 'self' https://fonts.googleapis.com","content-type":"application/json; charset=utf-8","strict-transport-security":"max-age=15768000","x-frame-options":"DENY","x-xss-protection":"1; mode=block","x-download-options":"noopen","x-content-type-options":"nosniff","cache-control":"no-cache","content-encoding":"gzip","vary":"accept-encoding"}}},"msg":"","time":"2015-09-17T15:28:50.366Z","v":0}
{"name":"id-webmaker-org","hostname":"zekrom.errietta.me","pid":410,"level":20,"req_id":"1442503731119:zekrom.errietta.me:410:ieodgrvq:10003","data":{"id":"1442503731119:zekrom.errietta.me:410:ieodgrvq:10003","method":"get","url":"/favicon.ico","agent":"Mozilla/5.0 (X11; CrOS x86_64 7262.52.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/45.0.2454.86 Safari/537.36"},"msg":"","time":"2015-09-17T15:28:51.120Z","v":0}
{"name":"id-webmaker-org","hostname":"zekrom.errietta.me","pid":410,"level":20,"req_id":"1442503731119:zekrom.errietta.me:410:ieodgrvq:10003","data":{"msec":1.9582271575927734},"msg":"","time":"2015-09-17T15:28:51.125Z","v":0}

A more friendly error should be shown:

id.webmaker.org/lib/oauth-db.js

Line 18 in ccb60ee

return callback(err);

can be wrapped to catch it.