Release of Jedi 0.18.0

[Dave Halter]

0.18.0 (2020-12-25)
+++++++++++++++++++

- Dropped Python 2 and Python 3.5
- Using ``pathlib.Path()`` as an output instead of ``str`` in most places:
- ``Project.path``
- ``Script.path``
- ``Definition.module_path``
- ``Refactoring.get_renames``
- ``Refactoring.get_changed_files``
- Functions with ``@property`` now return ``property`` instead of ``function``
in ``Name().type``
- Started using annotations
- Better support for the walrus operator
- Project attributes are now read accessible
- Removed all deprecations

This is likely going to be the last minor release before 1.0.