* copy() (breaking change): remove the option to pass keyword
arguments (which were present as key/value pairs in the copy).
Now the method doesn't take any arguments (it behaves the same
as a normal dict).
* Python versions: drop Python 3.7 support
* Typing: fixes
- Make the key covariant. Thanks to @spacether for the PR #244
- Fix key/value typing missing for ImmutableOrderedDict
OBS-URL: https://build.opensuse.org/package/show/devel:languages:python/python-immutabledict?expand=0&rev=8