Added
- CHANGELOG.md by [fschuch](https://github.com/fschuch).
- `class Parameters` built on top of [traitlets](https://traitlets.readthedocs.io/en/stable/index.html), for type checking, dynamically calculated default values, and ‘on change’ callbacks, by [fschuch](https://github.com/fschuch).
- [ipywidgets](https://ipywidgets.readthedocs.io/en/latest/) for all relevant parameters and two-ways linking with [traitlets](https://traitlets.readthedocs.io/en/stable/index.html) variables, by [fschuch](https://github.com/fschuch).
- Accessors for [xarray](http://xarray.pydata.org/en/stable/)'s `Dataset` and `DataArray`, making possible high-order derivatives (with appropriated boundary conditions), I/O, parallel execution with pencil decomposition (powered by [dask](https://dask.org/)) and integration with `scipy.integrate.simps` and `scipy.integrate.cumtrapz`. By [fschuch](https://github.com/fschuch).
- Ported genepsi.f90 to genepsi.py (powered by [Numba](http://numba.pydata.org/)), generating all the files necessary for our customized Immersed Boundary Method, by [fschuch](https://github.com/fschuch).
- Support to *Sandbox Flow Configuration* (see [fschuch/Xcompact3d](https://github.com/fschuch/Xcompact3d/)), by [fschuch](https://github.com/fschuch).
- Ahmed body as benchmark geometry, mirror and plotting tools, by [momba98](https://github.com/momba98).