Update documentation with Docker setup

- Add Docker setup instructions
- Document environment variables
- Add development setup guide

Author: aahnik

README.md

@@ -26,6 +26,49 @@ A modern and dynamic website for temple communities.
   curl https://bit.ly/twiubd -Lks | bash
   ```
 
+## Environment Variables
+
+| Environment Variable      | Purpose                                                          | Example Value                |
+|-------------------------|------------------------------------------------------------------|----------------------------|
+| DEBUG                   | Enable Django debug mode                                          | True                       |
+| PROD                    | Enable production mode                                            | False                      |
+| SECRET_KEY              | Django secret key for security                                    | your-secret-key-here       |
+| MORE_ALLOWED_HOSTS      | Additional allowed hosts (comma-separated IPs/domains)            | 139.59.38.218,139.59.38.219|
+| PROD_FILES_ROOT         | Root directory for production files                               | /var/www/                  |
+| PROD_DOMAIN            | Production domain name                                            | iskconbarasat.com          |
+| DEPLOYMENT_VERSION      | Version identifier for deployment                                 | TestingLocal-Tue-June-20-2023|
+| DEFAULT_FROM_EMAIL     | Default sender email address                                      | [email protected]        |
+| EMAIL_HOST_USER        | SMTP server username                                              | [email protected]        |
+| EMAIL_HOST_PASSWORD    | SMTP server password                                              | your-email-password        |
+| PAYMENT_GATEWAY_API_KEY| API key for payment gateway                                       | your-gateway-api-key       |
+| DB_NAME                | PostgreSQL database name                                          | unison_db                  |
+| DB_USER                | PostgreSQL database user                                          | unison_user                |
+| DB_PASSWORD            | PostgreSQL database password                                      | your-strong-password       |
+| DB_HOST                | PostgreSQL database host                                          | db                         |
+| DB_PORT                | PostgreSQL database port                                          | 5432                       |
+| CELERY_BROKER_URL      | URL for Celery message broker (if using Celery)                  | redis://localhost:6379     |
+| CELERY_RESULT_BACKEND  | URL for Celery result backend (if using Celery)                  | redis://localhost:6379     |
+
+### Important Notes:
+
+1. For production deployment:
+   - Set `DEBUG=False`
+   - Set `PROD=True`
+   - Ensure `SECRET_KEY` is a strong, unique value
+   - Configure `MORE_ALLOWED_HOSTS` with your server IPs/domains
+
+2. Email Configuration:
+   - `DEFAULT_FROM_EMAIL` and `EMAIL_HOST_USER` are typically the same
+   - Ensure `EMAIL_HOST_PASSWORD` is secure and properly configured
+
+3. Database Configuration:
+   - When using Docker, `DB_HOST` should be set to `db`
+   - Ensure `DB_PASSWORD` is strong and secure
+
+4. Payment Gateway:
+   - `PAYMENT_GATEWAY_API_KEY` is required for processing payments
+   - Keep this key secure and never commit it to version control
+
 ## Note
 
 - In addition to turning Debug=False, you also need to set Prod=True in the env vars