tweaks eslint rules, fixes gulp-eslint, adds some comments

website/src/middlewares/api-v3/errorHandler.js

@@ -1,21 +1,22 @@
 'use strict';
 
-// The error handler middleware that handles all errors 
+// The error handler middleware that handles all errors
 // and respond to the client
 let logger = require('../../libs/api-v3/logger');
 let errors = require('../../libs/api-v3/errors');
 let CustomError = errors.CustomError;
 let InternalServerError = errors.InternalServerError;
 
-module.exports = function (err, req, res, next) {
+module.exports = function errorHandlerMiddleware (err, req, res, next) {
   // Log the original error with some metadata
   let stack = err.stack || err.message || err;
+
   logger.error(stack, {
     originalUrl: req.originalUrl,
     headers: req.headers,
     body: req.body
   });
-  
+
   // In case of a CustomError class, use it's data
   // Otherwise try to identify the type of error (mongoose validation, mongodb unique, ...)
   // If we can't identify it, respond with a generic 500 error