* Add new `voigtfit` function
* All, fitting functions are optimized and fixed. Some parameters were added and removed.
* `autocorrelation` and `cross-correlation` functions for signal analysis.
* `derivative` function is included
* `peaksimilarity` function for peak alignment.
* A bug in baseline functions were one spectras was solved as many was fixed. Just in some cases, the list was processed as `[[a], [a], [a],..., [a]]` instead of `[a, a, a,..., a]`.
* New examples are added to the `docs`.
* Some data come in reverse order. A function `reverse` is now included to reverse vectors and lists of vectors.
* In `normsum` you can now choose a specific range of the vector to which normalize its sum to 1.
* A bug in `fwhm` for multiple spectras was fixed. Parameter `alpha` is included now to change the height of the full width.
**Full Changelog**: https://github.com/spectrapepper/spectrapepper/compare/v0.1.5...v0.1.6