allow upload_data_package to overwrite files

[RobLBaker]

Currently, upload_data_package() function will not allow you to upload any files if the reference already had files attached to it.

Allow this function to selectively detach existing files & replace them.

this way if people find errors or make changes based on data package reviewer feedback, they can still use this function to re-upload the newest version of their files.

[RobLBaker]

Closing and moving issue to EMLeditor