Update .env

Add possibility to use GPT4 for CHATGPT PLUS member

Update customAgent.py with GPT4

Update pythonAgent.py with GPT4

Update csvAgent.py with GPT4

Add GPT4 on ChatGPTAPI.py

Update pyChatGPT.py

add GPT4 to MetaPrompt.py

add GPT4 to AUTOGPT.py

Add GPT4 to BABYAGI.py

add GPT4 use to .env

Add GPT4 to ChatGPTAPI.py

Fix GPT4 pyChatGPT.py

Select GPT4 if user has ChatGPT Plus by Erol444

set a default path_csv - from jianboy/main