document OPENAI_API_HOST and OPENAI_ORGANIZATION (#429)

README.md

@@ -115,6 +115,8 @@ When deploying the application, the following environment variables can be set:
 | Environment Variable | Default value | Description |
 | --------------------- | ------------------------------ | ------------------------------------------------------- |
 | OPENAI_API_KEY | | The default API key used for authentication with OpenAI |
+| OPENAI_ORGANIZATION | | Your OpenAI organization ID |
+| OPENAI_API_HOST | `https://api.openai.com` | Base url of the OpenAI API |
 | DEFAULT_MODEL | `gpt-3.5-turbo` | The default model to use on new conversations |
 | DEFAULT_SYSTEM_PROMPT | [see here](utils/app/const.ts) | The default system prompt to use on new conversations |
 | GOOGLE_API_KEY | | See [Custom Search JSON API documentation][GCSE] |