Save Geo files to a temporary file and rename after success

Merged Stan Hu requested to merge sh-geo-fix-file-transfer-empty-files into master

The secondary would be filled with empty files even if the download was unsuccessful. Instead, we save the file to a temporary directory and rename only upon success.

Also improves the logging to use geo.log.

Closes #3618 (closed), #3242 (closed)

Edited by Stan Hu