0.4.0

This is version 0.4.0 of openPMD-viewer.

This new version includes:

• support for 1D data
• an additional option use_field_mesh when plotting the particle. When set
  to True, this option uses information from the field mesh to choose the parameters of the particle histograms (esp. the bins). This is useful in order to avoid plotting/binning artifacts (aliasing) when the particles are evenly spaced.

In addition, the package opmd_viewer now has an attribute __version__.