Use python-dotenv for environment variables.

PyCharm did not load conda environment variables.

.gitignore

@@ -0,0 +1 @@
+/.env

README.md

@@ -20,29 +20,9 @@ To install:
     conda activate straw2analysis
     ```
 
-2. Follow [the instructions](https://docs.conda.io/projects/conda/en/latest/user-guide/tasks/manage-environments.html#saving-environment-variables) to set DB_PASSWORD as the environment variable.
+2. Provide an .env file to be used by `python-dotenv` which should be placed in the top folder of the application 
+   and should have the form:
    
-    In short, use:
-
-    ```shell
-    cd $CONDA_PREFIX
-    mkdir -p ./etc/conda/activate.d
-    mkdir -p ./etc/conda/deactivate.d
-    touch ./etc/conda/activate.d/env_vars.sh
-    touch ./etc/conda/deactivate.d/env_vars.sh
    ```
-    and then edit `./etc/conda/activate.d/env_vars.sh` as follows:
+   DB_PASSWORD=database-password
-   
-    ```bash
-   #!/bin/sh
-   
-   export DB_PASSWORD='database-password' 
-   ```
-   
-    and `./etc/conda/deactivate.d/env_vars.sh` as follows:
-
-    ```bash
-   #!/bin/sh
-   
-   unset DB_PASSWORD 
    ```