Fix Version/s: None
DM-27784, any QuantumGraphs written out with save() now needs to have the extension .qgraph.
Change ctrl_bps code to name the QuantumGraph files *.qgraph. If any comments refer to the QuantumGraph's storage as a pickle file, fix the comments. Check the documentation for references to QuantumGraph and pickle file. For example, if there's an example line for starting from a QuantumGraph, change it to start with qgraph.
The saving of intermediate BPS steps as pickle files should not be changed as part of this ticket.
- is triggered by
DM-27784 Add ability to load select nodes from a QuantumGraph
Changes good to merge.