Dtools-datastructures

* first Version uploaded to PyPI
* https://pypi.org/project/grscheller.datastructures/
* Install from PyPI
* $ pip install grscheller.datastructures==0.2.1.0
* $ pip install grscheller.datastructures for top level version
* Install from GitHub
* $ pip install git+https://github.com/grscheller/datastructuresv0.2.1.0
* pytest made a dependency
* useful & less confusing to developers and end users
* good for systems I have not tested on
* prevents another pytest from being picked up from shell $PATH
* using a different python version
* giving "package not found" errors
* for CI/CD pipelines requiring unit testing

* First version able to be installed from GitHub with pip
* $ pip install git+https://github.com/grscheller/datastructuresv0.2.0.2

* First failed attempt to make package installable from GitHub with pip

* BREAKING API CHANGE!!!
* Stack push method now returns reference to self
* Dqueue pushL & pushR methods now return references to self
* These methods used to return the data being pushed
* Now able to "." chain push methods together
* Updated tests - before making API changes
* First version to be "released" on GitHub

* grscheller.datastructures moved to its own GitHub repo
* https://github.com/grscheller/datastructures
* GitHub and PyPI user names just a happy coincidence

* Package implementing data structures which do not throw exceptions
* Did not push to PyPI until version 0.2.1.0
* Initial Python grscheller.datastructures for 0.1.0.0 commit:
* dqueue - implements a double sided queue class Dqueue
* stack - implements a LIFO stack class Stack