Roundtrip conversion ipynb to python inserts a newline

[goerz]

This is using https://github.com/qucontrol/krotov/blob/f1082fe129abd609ecac25e57e0737066a599cd7/docs/notebooks/01_example_simple_state_to_state.ipynb, which is a notebook that contains no jupytext metadata:

> jupytext --to=py 01_example_simple_state_to_state.ipynb
  [jupytext] Reading 01_example_simple_state_to_state.ipynb
  [jupytext] Writing 01_example_simple_state_to_state.py
> jupytext --to=notebook --update 01_example_simple_state_to_state.py
  [jupytext] Reading 01_example_simple_state_to_state.py
  [jupytext] Writing 01_example_simple_state_to_state.ipynb (destination file updated)
> git diff 01_example_simple_state_to_state.ipynb
  nbdiff /var/folders/ll/rgszt4s525s2xtv8rr60lqz40000gn/T//Fjbgla_01_example_simple_state_to_state.ipynb docs/notebooks/01_example_simple_state_to_state.ipynb
  --- /var/folders/ll/rgszt4s525s2xtv8rr60lqz40000gn/T//Fjbgla_01_example_simple_state_to_state.ipynb  2019-01-29 22:31:01.546437
  +++ docs/notebooks/01_example_simple_state_to_state.ipynb  2019-01-29 22:30:54.699366
  ## modified /cells/26/source:
  @@ -5,4 +5,4 @@ def plot_population(result):
       ax.legend()
       ax.set_xlabel('time')
       ax.set_ylabel('population')
  -    plt.show(fig)

  +    plt.show(fig)

I would expect this roundtrip conversion to leave the notebook completely unchanged.

[mwouts]

This should be OK now in 1.0.0-rc1. Can you please confirm @goerz ? Thanks

[goerz]

Same as #165: the bug seems fixed, by the json has a stripped newline. I'll close here, but leave #165 open.