1. remove add-vertex* and remove-vertex* that contradicted the documentation.
2. graphs use hash-sets of edges instead of hashtables of {edge,edge} pairs.
3. make graphs:closure work like classes:closure, use in classes.
						
					
				
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| .. | ||
| authors.txt | ||
| graphs-docs.factor | ||
| graphs-tests.factor | ||
| graphs.factor | ||
| summary.txt | ||
| tags.txt | ||