Custom vectorizers

[dirkkul]

Closes #1138
Closes #950

This adds the possibility to add custom vectorzers, rerankers and generative modules to the collection config.
The syntax is

Configure.Generative.custom(
            "generative-whatever", module_config={"temperature": 0.5}
        )
Configure.Reranker.custom(
            "reranker-whatever", module_config={"model": "whatever"}
        )
Configure.Vectorizer.custom(
            "text2vec-whatever", module_config={"vectorizeClassName": False}
        )
Configure.NamedVectors.custom(
                "name", module_name="text2vec-contextionary", module_config={"vectorizeClassName": False}
            )

in addition, the client can now also handle returns with modules that it does not know

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 95.15152% with 8 lines in your changes missing coverage. Please review.

Project coverage is 94.61%. Comparing base (42fb96c) to head (a6aef0a).
Report is 80 commits behind head on main.

Files	Patch %	Lines
weaviate/collections/classes/config_methods.py	78.57%	6 Missing ⚠️
integration/test_collection_config.py	98.41%	1 Missing ⚠️
weaviate/collections/classes/config_vectorizers.py	96.66%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1152      +/-   ##
==========================================
- Coverage   94.68%   94.61%   -0.07%     
==========================================
  Files         190      193       +3     
  Lines       18932    19197     +265     
==========================================
+ Hits        17926    18164     +238     
- Misses       1006     1033      +27     

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