Remove keys.py and replace with python-dotenv.

- Removed `keys.py`.
- Added `.env.template`.
- Added `.env` to `.gitignore`.
- Updated various files that imported `keys` to use `os.getenv` instead.
- Updated `requirements.txt` dependencies.
- Updated README.md with instructions on setting up environment variables.

This change improves security, flexibility, and makes it easier to use Auto-GPT in notebooks. Environment variables are stored in `.env` and loaded via `load_dotenv()` in `scripts/main.py`.

scripts/main.py

@@ -11,6 +11,11 @@ import speak
 from enum import Enum, auto
 import sys
 from config import Config
+from dotenv import load_dotenv
+
+
+# Load environment variables from .env file
+load_dotenv()
 
 
 class Argument(Enum):