Changed storage of calculated data from implicit to explicit.

setup.py

src/robofish/io/__init__.py

src/robofish/io/app.py

src/robofish/io/entity.py

src/robofish/io/file.py

tests/resources/nan_test.hdf5

tests/resources/valid_1.hdf5

tests/resources/valid_2.hdf5

tests/robofish/io/test_app_io.py