Add instructions for replay to replay scripts

[ChrisKeefe]

Instructions for making scripts executable are written to script headers, but documentation is limited for users who care only to run a script that has already been prepared according to these instructions.

It would be straightforward to add a section on how to run a script that has been so adapted, maybe below a horizontal rule so that people prepping reproducibility supplements can just delete one section of instructions.

E.g.

# 1. Add some filepaths to adapt this script for replay
# 2. Do some other stuff
...
# N. Delete the instructions above this line if you have already completed them and plan to share this script
------------------------------------------------------------------------------------------------------------------------------------------
# 1. Navigate to the location of this script
# 2. Make sure the input data and metadata file paths (e.g. on the import lines) point to the data you plan to replay from
# 3. use the command bash <this script> to run the script