* updating the implementation of /v1/chat/completions to use the generic provider interfaces
* saving changes, although we will need a small re-factor after this as well
* more refactoring changes, getting close
* more refactoring changes to avoid unecessary re-direction and duplication
* more clean up
* more refactoring
* more refactoring to clean code and make stream_context.rs work
* removing unecessary trait implemenations
* some more clean-up
* fixed bugs
* fixing test cases, and making sure all references to the ChatCOmpletions* objects point to the new types
* refactored changes to support enum dispatch
* removed the dependency on try_streaming_from_bytes into a try_from trait implementation
* updated readme based on new usage
* updated code based on code review comments
---------
Co-authored-by: Salman Paracha <salmanparacha@MacBook-Pro-2.local>
Co-authored-by: Salman Paracha <salmanparacha@MacBook-Pro-4.local>
