Final todo list for NCrystal 4.0.0

[tkittel]

Getting close to releasing NCrystal 4.0.0, collecting a few scattered final TODO items here:

#FIXME Address all of the following for the release:

• Make sure pypi.yml omly triggers for even patch numbers (in addition, we
  should only create even tags!). Document this policy.

• We should have a way to determine what version of NCrystal a given plugin was
  built against, so we can error on incompatibilities.

• Make sure pull requests have check boxes on top with stuff like "did you add a
  test", "did you mention any open issues this is linked to", etc.

• ncdevtool/CI improvements

  • "ncdevtool find" mode seems broken.
  • import sb_devtools_gdb/valgrind?
  • check shebangs consistent
  • check files left outside dirs
  • use inspect module to find missing docstrings in modules and functions
  • python coverage testing.
  • Open issue about migrating more tests from ncrystaldev repo
  • Compile and test also dmsc:ncrystaldev nclong pkgs.
  • Guard against DOS line endings.

• Support (and test) windows paths starting with "\?", as well as shared
  directories starting with double slashes.

• plugin docs should contain this info:
  Make CrysText plugin ready for ncrystal v4 highness-eu/ncplugin-CrysText#1 (comment)

conda install ncrystal-all
conda install ncrystal-plugin-support

• Update wiki to point at HEAD rather than master

• plugindb.yml: cpp check all plugins? And test all the pip install git+... urls.

• We should remove the gitref: tags in plugin_database.yml for mctools/ncrystal.

• We need a CI which tests that there are no missing NCRYSTAL_API declations.