Changed transformers_client design so it can support most (all?) HuggingFace models

[adjahossoualexandre]

New design

TransformerClient into 3 client classes:

1. TransformerEmbeddingModelClient

• Merger of TransformerEmbedder and TransformerClient

2. TransformerRerankerModelClient

• Merger of TransformerReranker and TransformerClient

3. TransformerLLMModelClient

• Merger of TransformerLLM and TransformerClient

Pros:

• Abstracts model/tokenizer initialisation as well as inference code
• Hence, most of the time, the only customization needed is to change some parameters during client instantiation
• Works with many different model architectures (example here)
• Make the code easier to read and more maintainable since each class takes care of only one client
• Easier to customize for users as it removes the need for model SDKs
• Removes the need to check whether a model is supported or not

Cons:

• The tradeoff here would be to couple inference code with the response and api kwargs handling.