Allow dall-e-3 model for image generation

[rxaviers]

trafficstars

Open AI have just updated their API and now allows dall-e-3 image generation. https://platform.openai.com/docs/guides/images?context=node

On this change, the request has been updated to also pass model.

Usage:

chatgpt -m dall-e-3 --size 1024x1024 "image: <image description>"

[mountaineerbr]

While this is not implemented here, you may want to try my chatgpt.sh shell script which supports dall-e-3 model for image generations by defaults.