* First attempt at register/deregister machinery for envvars
* Added detailed docstring, simplified ensurers
Also added some type checking that became clear from docstring writing.
* Changes in response to @scopatz review
Simplified kwarg names.
* defaultval -> default
* Created new Var namedtuple, as well as DEFAULT_VARS
We should now delete DEFAULT_ENSURERS, DEFAULT_VALUES, DEFAULT_DOCS, and
refactor Env to use the new single namedtuple and the DEFAULT_VARS dict
* Removed DEFAULT_ENSURERS, DEFAULT_VALUES, DEFAULT_DOCS
Now need to edit Env to use new DEFAULT_VARS, Var namedtuple
* Finished updating Env object to use new combined Var
Also made corresponding changes elsewhere ensurer was used
* Working on test failures
* More fixes in light of test failures
* Set default values for Var in register.
There's a bit of duplication here, but makes for a cleaner function.
* Black reformatting on environ.py
* Removed history replay
* Added register tests
* Added addtional deregistration test
* Removed all replay references, in docs too
* Added news item for env-reg-dereg
* trigger rebuild
* doc fix
* more doc fixes
* again
* attr names
* reorder imports
* fix flake error
Co-authored-by: Anthony Scopatz <scopatz@gmail.com>
