* added -f to all Mac and Linux rm commands
* Function renames: create_download_file_to_file_command -> download_url_to_file
                                create_download_from_config_file -> download_from_config_file
                                add_dl -> add_download_url
 * CopyTool classes and DownloadTool classes have platformHelper member, initialized in super and so now all have __init__ methods
 * Windows: exit_if_error is added after most created batch file lines