Update Environment Variables

Environment-Variables.md

@@ -5,40 +5,72 @@ This wiki covers the environment variables used in this application, their purpo
 
 #### `BOT_TOKEN`
 
+**Required / No Default**
+
 ### Security
 
 #### `DEBUG`
 
+**Optional / Default `False`**
+
 #### `SECRET_KEY`
 
+**Optional / Default `unsecure-default-secret-key`**
+
 ### Discord App
 
 #### `DISCORD_KEY`
 
+**Required / No Default**
+
 #### `DISCORD_SECRET`
 
+**Required / No Default**
+
 #### `DISCORD_OAUTH2_URL`
 
+**Required / No Default**
+
 #### `DISCORD_INVITE_URL`
 
+**Required / No Default**
+
 #### `DISCORD_REDIRECT_URL`
 
+**Required / No Default**
+
 #### `DISCORD_API_URL`
 
+**Required / No Default**
+
 ### Database
 
 #### `DB_ENGINE`
 
+**Optional / Default `None`**
+
+If `None`, the other database environment variables will be ignored, and an sqlite database will be used in the project root, named `db.sqlite3`.
+
 #### `DB_NAME`
 
+**Optional / No Default**
+
 #### `DB_USER`
 
+**Optional / No Default**
+
 #### `DB_PASS`
 
+**Optional / No Default**
+
 #### `DB_HOST`
 
+**Optional / No Default**
+
 #### `DB_PORT`
 
+**Optional / No Default**
+
 ### Extras
 
 #### `SUPERUSER_IDS`