include instructions for adding .env file with sqlpad username and pa…

…ssword

README.md

@@ -7,3 +7,8 @@ Installation:
 * Clone the repository and navigate to the root folder, HydraDx-simulations
 * In terminal, enter 'pip install -r requirements.txt'
 * Alternatively, open the project folder in PyCharm, and you'll be prompted to create a virtual environment for this project. 
+* If you want to pull data from SQLPad, add a .env file to ./hydradx/model/ with the following contents:
+```
+SQLPAD_USERNAME=<your username>
+PASSWORD=<your password>
+```