This PR conceptually changes how node filtering edge rules are implemented.

Previously: edge rules filtered nodes and the edges themselves.

Changed logic: Edge rules filter nodes. Edges themselves are not filtered by node filtering rules. Edges are only trimmed to remove orphaned nodes caused by node filtering.

• Filter edges by edge rule -- filteredEdges
• Filter nodes by filteredEdges -- filteredNodes
• Trim all network edges to remove any orphaned edges caused by removed nodes. This removes edges that make the network invalid. -- validEdges
• Return filteredNodes and validEdges

Tests added and existing tests updated to cover conceptual changes.

Todo:

• Update language in documentation article to reflect this conceptual change
• Make equivalent change in Interviewer