* Updated the use of NetworkX MultiDiGraph class and topographic metrics
* Added methods to groups links and nodes into segments based on the location of isolation valves
* Updated several graphics functions
* Updated the mass consumed water security metric to include a detection limit
* Updated skeletonize and other network morphology functions to be more efficient when using large networks
* Added a sensor placement optimization example
* Updated documentation and testing
See [WNTR version 0.2.2 Release Notes](https://wntr.readthedocs.io/en/latest/whatsnew.html) for more details.