* tests | add start of small test suite

* start with atomic_distribution

* tests | add canonical_configuration

* tests | add crystal_structure_info

* tests | missing files for atomic_distribution

* tests | add extract_forceconstants

* tests | add generate_structure

* tests | add lineshape

* tests | add pack_simulation

* test | phonon_dispersion_relations

* tests | add thermal_conductivity

* tests | shortcut to do everything

* tests | add requirements.txt

* tests | fix

* tests | mention in INSTALL.md and CONTRIBUTING.md

* tests | add anharmonic_free_energy

* tests | fix

* tests | update dispersion test

* tests | use np.testing.assert_allclose

* tests | fix, hide thermal_conductivity for the time being

* tests | remove BZ test --> degeneracy

* tests | fix thermal_conductivity test

* needs more realstic forceconstants to work

* tests | fix test_thermal_conductivity

* losen requirements a little, allow 1% difference

* Install | point out the bashrc lines

* tests | add missing dependency for reading hdf5

* tests | use xarray[io] for handling the file io

probably a little overkill