Add script for applying the offline-mode to the current branch

[jimchamp]

Creates script that, when executed, applies the offline-mode branch's changes to the branch that is currently checked out.

To apply these changes locally, do the following:

1. Ensure that you are on the correct branch.
2. Run docker compose exec -uroot web ./scripts/apply_offline_mode.sh

The script will then download and apply the changes to your current branch. To undo these changes, add a --reverse flag to the command:
docker compose exec -uroot web ./scripts/apply_offline_mode.sh --reverse

Technical

Testing

Screenshot

Stakeholders

[scottbarnes]

Looks good to me, both applying and reversing.