add bash script to install docker and TEKDB on Linux

[paigewilliams]

Work in progress! Writing a bash script to run on Linux to install docker and the TEKDB repo, and start the docker containers.

How to test:

1. Create a .env.prod file with your environment variables in an accessible location on your Linux instance. .env.prod should contain the following environment variables

   
SECRET_KEY= # a random 50+ character string used for Django.You can generate this yourself or use a tool like [this](https://builtwithdjango.com/tools/django-secret/) to generate one for you.
ALLOWED_HOSTS= # IP address you want the app to run on 
SQL_ENGINE=django.contrib.gis.db.backends.postgis
SQL_DATABASE= # database name, ex: tekdb
SQL_USER= #database user, ex: postgres
SQL_PASSWORD= # database password
SQL_HOST=db
SQL_PORT=5432
WEB_IMAGE=ghcr.io/ecotrust/tekdb/web 
CELERY_BROKER_URL=redis://redis:6379/0
GIS_USER_PASSWORD= # password for user named ‘gis’ which has permissions for accessing tables with spatial data

2. Copy the scripts/Linux/install-docker-env.sh file to an accessible location on your Linux instance. Run ./install-docker-env.sh <file path to env.prod file>

3. View the TEKDB application running on your specified IP address!