Gracefully handle Multer file type errors

[kasipavankumar]

Issue

Currently we are not handling the exceptions thrown by Multer during the filter file operation. Instead, we just delegate an HTML error to the client.

Point of issue

api/source/middleware/process-package.js

Line 12 in 522801f

return callback(new Error(messages.PACKAGE_FILE_TYPE))

Solution

Yet to figure.