Updating documentation
Using uuid library to check if string is uuid
Removing unused code
Moving validParams and validFiles lists to one location (inside util).  Also, if copy_data parameter is set, make sure user has read access to that node before calling Update
Added CopyUpload type to Update function.
Moving validParams and validFiles lists to one location (inside util).  Also, if copy_data parameter and upload file is given exit with error and delete temporary file.
Moving validParams and validFiles lists to one location (inside util).