Cyclophaser

- Version fixes

Documentation Enhancements
- **Expanded Installation Instructions**: Added comprehensive steps for installing the package, including guidance for setting up with `pip` and `conda` environments.
- **Clarified Statement of Need**: Removed the "Statement of Need" section from the documentation, as it is now effectively covered in the accompanying publication. Updated both the README and documentation homepage to provide a clear explanation of the package's purpose, emphasizing that CycloPhaser requires a pre-existing vorticity series. Detailed guidance added on obtaining vorticity data from tracking packages and reanalysis sources.
- **Added Citations**: Included references to the CycloPhaser paper (under review) and to *International Journal of Climatology* to give users additional context and use cases for the package.
- **Example Track File**: Added an example input track file format to the documentation, illustrating the expected structure for time, latitude, and longitude columns.
- **Functionality Documentation**: Extended docstrings for other accessible functions to improve understanding of each function's role and usage.

Fixed
- Corrected a typo in the `conf.py` file within the `docs` folder: changed "Cyclophaser" to "CycloPhaser" in the `project` variable.

New Features and Improvements
- **User Warnings for Data Quality**:
- Added warnings to detect unexpected "residual" stages mid-series and gaps in detected periods. Warnings now indicate possible data quality issues and recommend adjusting pre-processing options.
- **Enhanced Documentation**:
- Expanded on the `x` parameter in `determine_periods` to clarify behavior when integers are provided, as well as acceptable input formats.

Code Refinements
- Removed redundant commented imports in `determine_periods.py`.
- Updated `requirements.txt` to avoid highly specific version constraints, improving compatibility with other packages in shared environments.

New Features
- **Hemisphere Support Argument**: Added `hemisphere` argument in `determine_periods` function. This enables users to specify `southern` or `northern` hemisphere data, with automatic sign inversion for the northern hemisphere. Improved compatibility with wind data by setting this option to "northern".

Documentation Improvements
- **Detailed Argument Descriptions**: Updated the `determine_periods` and `process_vorticity` functions' documentation to include specific units, guidelines, and recommendations for each parameter, enhancing usability.
- **Parameter Recommendations**:
- `use_filter`: Added usage guidelines based on data type and frequency. For example, recommended setting `use_filter='auto'` for ERA5 data.
- `replace_endpoints_with_lowpass`: Recommended setting a 24-hour window for hourly vorticity data.
- `use_smoothing` and `use_smoothing_twice`: Added detailed behavior of 'auto' settings and recommendations based on noise levels.
- `savgol_polynomial`: Explained ideal usage for smoothing based on noise level.
- `cutoff_low` and `cutoff_high`: Provided guidance for optimal values to filter out planetary and mesoscale influences in vorticity data.
- **Additional Usage Recommendations**: Included cases for using alternative data types like SLP and wind speed and noted expected behavior with phase transitions.
- **Error and Warning Details**: Updated documentation to clarify error conditions related to parameter constraints, particularly for `use_smoothing` and `savgol_polynomial`.

Code Adjustments
- **Spurious Oscillations Warning**: Added functionality to check for spurious oscillations at the start and end of filtered data, with a warning suggesting adjustments to `use_filter`, `replace_endpoints_with_lowpass`, or `use_smoothing` if detected.
- **`use_filter` Activation**: Clarified that passing an integer as the window length is necessary for activation.
- **Optional Smoothing**: Adjusted `use_smoothing` and `use_smoothing_twice` logic to handle `False` as a deactivation option, bypassing the smoothing process when set to `False`.
- **Savgol Parameter Warnings**: Implemented a check to raise an error if `savgol` window length is smaller than `savgol_polynomial`, ensuring valid parameter configurations.

Testing Enhancements
- **Output Verification in Tests**: Enhanced test cases to check not only for successful execution but also for expected output consistency. Created expected results for different configurations (`use_filter`, smoothing parameters, and hemisphere adjustments) and verified test output matches these expected results.
- **Suppression of Specific Warnings**: Suppressed spurious oscillation warnings in test cases to reduce unnecessary output during testing.

Bug Fixes
- **Normalization Clarification**: Resolved confusion regarding normalization in plots by noting that visualization normalization does not impact the core data analysis.

Documentation Update
- Clarified in the **API documentation** and **Usage Guide** that the `series` argument in the `determine_periods` function does not need to be in a specific unit.