quickplots/qp_driver.py: Fixed bug that fpath_fx was always determined automatically but not taken from fpath_fx settings.

pyicon/pyicon_IconData.py: Load more variables from grid file necessary for edge2edge_viavert calculations. Make zarea_fraction 3D.

notebooks/examp_oce_uvw_from_mass_flux.ipynb: Added notebook to derive centered velocities from edge mass_flux.

quickplots/pyicon_quickplots.py: Removed bug in timeseries plot when time steps at beginning or end should be omitted.

Updated section scripts corresponding to Helmuth's and Lennart's inuput: tool_icon_section_transport_mask_r2b4_r0004.py tool_icon_section_transport_mask_r2b6_r0004.py tool_icon_section_transport_mask_r2b8_r0004.py.

config_ckdtree/config_ckdtree_smtwv_oce.py: New script for SMT WAVE (and renamed old one as backup).

view/pyicon_view.py: Added doc string. Removed superficial option use_tgrid. Removed back wrt grid cropping call.

ci/requirements_py37.yml requirements_py38.yml: Adding dask-jobqueue and python-graphviz to requirements files.

pyicont_tb.py: Added some basic xarray features to time_averaging. Removed dtype=IcD.dtype from some functions which do not know IcD.

tools/tool_icon_section_transport_mask_r2b8_r0004.py: Added remplate file for r2b8 sections. These are not changed from r2b6, yet.

pyicon/quickplots/qp_driver.py: Allowing to specify a red_list or a green_list in config file to omit certain figure or to restrict to certain figures, respectively.