Cshelve

Added
- Logging support for the `cshelve`.
- Logging support for the `azure-blob` provider.

Added
- Pathlib support.

Improvement
- Documentation for the `cshelve` package.

Breaking Change
- The `azure-blob` is not installed by default. To install it, use `pip install cshelve[azure-blob]`.

Added
- Added a development container for streamlined development.
- Introduced `ConfigurationError` exception for handling provider configuration errors.
- Initialized project documentation.

Added
- In-memory provider

Improvement
- Tests refactored.
- Use in-memory provider for unit tests.
- Run examples in the CI pipeline.

Added
- Authentication methods for the azure-blob provider:
- Anonymous read-only access on public blob storage.
- Using Access key.