Sibila

- feat: Migrate hardcoded OpenAI model entries from OpenAIModel to 'res/base_models.json'.
- feat: OpenAI now accepts unknown models using defaults from 'openai:_default' key in 'res/base_models.json'.
- feat: Support OpenAI models with a limit on max_tokens output values, like "gpt-4-turbo-preview" (input ctx_len of 128k but only up to 4k output tokens).
- feat: Auto-discover maximum ctx_len in LlamaCppModel loaded files, when 0 is passed.
- feat: Add negative int factor mode to GenConf.max_tokens setting, allowing for a percentage of model's context length.
- fix: Add coherent error exceptions when loading local and remote models.
- fix: Correct interact() error when GenConf.max_tokens=0.
- fix: Correct several chat template formats.
- test: Add many new tests for gpt-3.5/4 and llama.cpp models.
- docs: Update tips section.

- feat: Split Models factory config in two levels: base definitions in sibila/res and Models.setup() loaded definitions from user folders. These levels never mix, but a fusion of the two is used for models/formats resolution. Only in this manner can "models" folder definitions be kept clean.
- fix: Option sibila formats -u is removed as result of the two-level Models factory.
- fix: Correct delete of link entries in models.json and formats.json, which was resolving to targets (and deleting them).
- fix: Raise ValueError when trying to generate from an empty prompt in LLamaCppModel.
- fix: Update Models to check linked entries when deleting.
- fix: Update template format discovery to work in more edge cases.
- test: Add test cases for sibila CLI and LlamaCppModel.

- feat: Improve template format discovery by looking in same folder for models/formats.json.
- fix: Update legacy importlib_resources reference.
- docs: Improve text.

- fix: Move base_models.json and base_formats.json to sibila/res folder.
- fix: Add base_models.json and base_formats.json to project build.
- fix: Correct .gitignore skipping valid files.
- docs: Update installation help and mentions to base_models/formats.json.

- feat: Added sibila CLI for models and formats management.
- feat: Added methods in Models class for CLI functionality.
- fix: Blacklisting character control set in JSON strings grammar.
- docs: Improved docs and added section about sibila CLI.
- docs: Added CLI example.

- feat: Improved documentation.
- feat: Model.known_models() returns a list of fixed known models or None if unlimited.
- feat: LlamaCppModel now also looks for the chat template format in a 'formats.json' file in the same folder as the model file.
- feat: Added GenConf.from_dict() and renamed asdict() to as_dict().
- fix: Creating a model entry in "models.json" with a genconf key was not being passed on model creation.