Curvilinear Datagrid is not displayed correctly

Created by: davidmnielsen

The datagrid is not displayed correctly, in this specific case for the curvilinear grid of MPIOM when trying the datagrid option at psy.plot.mapplot:

maps = psy.plot.mapplot(file_lr,
                        name='area',
                        cmap='Blues',
                        maskleq=0,
                        stock_img=True,
                        lonlatbox=[-180, 180, 60, 90],
                        extend='max',
                        load=True,
                        projection='northpole',
                        xgrid=False, ygrid=False,
                        clabel='{desc}',title='LR',
                        bounds=np.arange(0,10000000000,1000000000),
                        datagrid=dict(color='k', linewidth=0.1),
                        tight=True)

A full reproducible example is available at Github, with all the auxiliary files needed: https://github.com/davidmnielsen/gridcell_area