given an output object, filename, and zip file, write the output object
to the file, and then add to the zip file
Usage
add_to_zip(object, filename, zip_file)
Arguments
- object
the object to write
- filename
the file that it should be
- zip_file
the zip file to add to
Details
a directory created by tempdir is used to hold the file,
which is then added to the zip file.