Erlang server

[NelsonVides]

Allow for ProvidedCallback to return stop if manual handling was desired, as the AcceptCallback already does.

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• Read the contribution guidelines.
• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
• Run the following to build the project and update samples:

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  ./bin/utils/export_docs_generators.sh || exit
  

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  Commit all changed files.
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