Use gutenberg.server instead of hard-coded paths
[#83]: Removing Valum's fileuploader ...

Could conflicting .js be the reason for "this is not a constructor" error message
[#83]: Switching to Valum's original file uploader ...

Hoping it will help with the 'is not a constructor' message
[#83] Forgot to add fileuploader.js when removing other .js files
[#83]: Silly mistake - hard-coded path not removed