Polishes text by sending to Open AI. Select text. Then 'Polish' in the command pallet. Text will be updated in place.
To update API key. 'Set API Key' in command pallet.
You need to get an Open AI API key and enter when prompted.
 Allow user to set the system prompt and choose the model.  Tidy up this readme and code and publish  Have a mode to trigger on ". " or new line.