Make upload file size limit configurable

When using our internal webhdfs does not support large file secure write. We need to intentionally limit upload file size. Therefore, when using Hue to upload a big file, it will fail. We have found a hack fix to this by modifying the "sizeLimit" parameter in desktop/core/static/ext/js/fileuploader.js
However, we were not able to find an obvious way to add this option in the configuration file. It will be great if this is made configurable or please point us at the right place to fix this issue.