Freepaths

New in this release
- The ability to create more than one hot or cold sides
- Improving behavior of the hot side
- Minor fixes

New in this version
- Added ability to create thermal gradients in any direction by [placing the cold and hot sides at any boundary](https://anufrievroman.gitbook.io/freepaths/examples/thermal-gradients).
- Minor bug fixes

New in this version

- Complete rewrite of the simulator using more OOP oriented approach and better architecture.
- Implementing animations of phonon paths
- Switching to using input files from the user
- Providing examples of typical input files
- Improving phonon path storage, so that only scattering points are saved
- Implementing parabolic boundaries (Thanks to work of Dhanishtha Singh)