renaming files and allow for Sandbox download

upload_config: renamed to download_config (to avoid same name as in ir_upload)
IR_config_constants.py: renamed to IR_da_config_constants.py (to avoid same name as in ir_upload)
IR_image_tools.py, downloadversionIRdata.py, setup.py: adjusted import to IR_da_config_constants
download_config: parameter archivedb changed from boolean 'True'/'False' to string 'ArchiveDB'/'Test'/'Sandbox'
IR_da_config_constants.py: load target database from upload_config parameter archivedb and build archivepath from it