Add support for replicate [code in ticket]

[krrishdholakia]

Here's my code for replicate:

elif "replicate" in model: 
    prompt = " ".join([message["content"] for message in messages])
    output = replicate.run(
      model,
      input={
        "prompt": prompt,
      })
    print(f"output: {output}")
    response = ""
    for item in output: 
      print(f"item: {item}")
      response += item
    new_response = {
      "choices": [
        {
          "finish_reason": "stop",
          "index": 0,
          "message": {
              "content": response,
              "role": "assistant"
          }
        }
      ]
    }
    print(f"new response: {new_response}")
    response = new_response

[krrishdholakia]

PR added - #5